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Merged
merged 3 commits into from
Aug 11, 2023
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@Gelbpunkt Gelbpunkt commented Jul 23, 2023

See individual commit messages for more info

@Gelbpunkt Gelbpunkt changed the base branch from v6.5-rc-t to test_dsc July 28, 2023 16:29
@Gelbpunkt Gelbpunkt force-pushed the davinci branch 2 times, most recently from 51f4193 to 2addd56 Compare July 31, 2023 14:59
@Gelbpunkt Gelbpunkt changed the base branch from test_dsc to next July 31, 2023 15:01
@JIaxyga JIaxyga force-pushed the next branch 4 times, most recently from 60e8fd1 to 480e1ae Compare August 5, 2023 14:40
@Gelbpunkt Gelbpunkt marked this pull request as ready for review August 10, 2023 20:54
This is an updated version of the one published by goodix at
https://github.com/goodix/gtx8_driver_linux

Modifications:

- Adapt for changes in recent kernel versions
- Rename pinctrls to "default" and "sleep"
- Resolve some miscellaneous GCC warnings
- clang-formatted the entire driver
- Fix all typos reported by codespell
- Add support for avdd-gpio and avdd-load/vtouch-load from older
  versions (required for davinci (gt9886) to function)

Signed-off-by: Jens Reidel <[email protected]>
@JIaxyga JIaxyga merged commit 0679a60 into sm7150-mainline:next Aug 11, 2023
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JIaxyga commented Aug 11, 2023

Thanks!

JIaxyga pushed a commit that referenced this pull request Sep 8, 2023
The following processes run into a deadlock. CPU 41 was waiting for CPU 29
to handle a CSD request while holding spinlock "crashdump_lock", but CPU 29
was hung by that spinlock with IRQs disabled.

  PID: 17360    TASK: ffff95c1090c5c40  CPU: 41  COMMAND: "mrdiagd"
  !# 0 [ffffb80edbf37b58] __read_once_size at ffffffff9b871a40 include/linux/compiler.h:185:0
  !# 1 [ffffb80edbf37b58] atomic_read at ffffffff9b871a40 arch/x86/include/asm/atomic.h:27:0
  !# 2 [ffffb80edbf37b58] dump_stack at ffffffff9b871a40 lib/dump_stack.c:54:0
   # 3 [ffffb80edbf37b78] csd_lock_wait_toolong at ffffffff9b131ad5 kernel/smp.c:364:0
   # 4 [ffffb80edbf37b78] __csd_lock_wait at ffffffff9b131ad5 kernel/smp.c:384:0
   # 5 [ffffb80edbf37bf8] csd_lock_wait at ffffffff9b13267a kernel/smp.c:394:0
   # 6 [ffffb80edbf37bf8] smp_call_function_many at ffffffff9b13267a kernel/smp.c:843:0
   # 7 [ffffb80edbf37c50] smp_call_function at ffffffff9b13279d kernel/smp.c:867:0
   # 8 [ffffb80edbf37c50] on_each_cpu at ffffffff9b13279d kernel/smp.c:976:0
   # 9 [ffffb80edbf37c78] flush_tlb_kernel_range at ffffffff9b085c4b arch/x86/mm/tlb.c:742:0
   #10 [ffffb80edbf37cb8] __purge_vmap_area_lazy at ffffffff9b23a1e0 mm/vmalloc.c:701:0
   #11 [ffffb80edbf37ce0] try_purge_vmap_area_lazy at ffffffff9b23a2cc mm/vmalloc.c:722:0
   #12 [ffffb80edbf37ce0] free_vmap_area_noflush at ffffffff9b23a2cc mm/vmalloc.c:754:0
   #13 [ffffb80edbf37cf8] free_unmap_vmap_area at ffffffff9b23bb3b mm/vmalloc.c:764:0
   #14 [ffffb80edbf37cf8] remove_vm_area at ffffffff9b23bb3b mm/vmalloc.c:1509:0
   #15 [ffffb80edbf37d18] __vunmap at ffffffff9b23bb8a mm/vmalloc.c:1537:0
   #16 [ffffb80edbf37d40] vfree at ffffffff9b23bc85 mm/vmalloc.c:1612:0
   #17 [ffffb80edbf37d58] megasas_free_host_crash_buffer [megaraid_sas] at ffffffffc020b7f2 drivers/scsi/megaraid/megaraid_sas_fusion.c:3932:0
   #18 [ffffb80edbf37d80] fw_crash_state_store [megaraid_sas] at ffffffffc01f804d drivers/scsi/megaraid/megaraid_sas_base.c:3291:0
   #19 [ffffb80edbf37dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   #20 [ffffb80edbf37dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   #21 [ffffb80edbf37de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   #22 [ffffb80edbf37e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   #23 [ffffb80edbf37ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   #24 [ffffb80edbf37ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   #25 [ffffb80edbf37ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   #26 [ffffb80edbf37f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   #27 [ffffb80edbf37f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

  PID: 17355    TASK: ffff95c1090c3d80  CPU: 29  COMMAND: "mrdiagd"
  !# 0 [ffffb80f2d3c7d30] __read_once_size at ffffffff9b0f2ab0 include/linux/compiler.h:185:0
  !# 1 [ffffb80f2d3c7d30] native_queued_spin_lock_slowpath at ffffffff9b0f2ab0 kernel/locking/qspinlock.c:368:0
   # 2 [ffffb80f2d3c7d58] pv_queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/paravirt.h:674:0
   # 3 [ffffb80f2d3c7d58] queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/qspinlock.h:53:0
   # 4 [ffffb80f2d3c7d68] queued_spin_lock at ffffffff9b8961a6 include/asm-generic/qspinlock.h:90:0
   # 5 [ffffb80f2d3c7d68] do_raw_spin_lock_flags at ffffffff9b8961a6 include/linux/spinlock.h:173:0
   # 6 [ffffb80f2d3c7d68] __raw_spin_lock_irqsave at ffffffff9b8961a6 include/linux/spinlock_api_smp.h:122:0
   # 7 [ffffb80f2d3c7d68] _raw_spin_lock_irqsave at ffffffff9b8961a6 kernel/locking/spinlock.c:160:0
   # 8 [ffffb80f2d3c7d88] fw_crash_buffer_store [megaraid_sas] at ffffffffc01f8129 drivers/scsi/megaraid/megaraid_sas_base.c:3205:0
   # 9 [ffffb80f2d3c7dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   #10 [ffffb80f2d3c7dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   #11 [ffffb80f2d3c7de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   #12 [ffffb80f2d3c7e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   #13 [ffffb80f2d3c7ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   #14 [ffffb80f2d3c7ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   #15 [ffffb80f2d3c7ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   #16 [ffffb80f2d3c7f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   #17 [ffffb80f2d3c7f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

The lock is used to synchronize different sysfs operations, it doesn't
protect any resource that will be touched by an interrupt. Consequently
it's not required to disable IRQs. Replace the spinlock with a mutex to fix
the deadlock.

Signed-off-by: Junxiao Bi <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Mike Christie <[email protected]>
Cc: [email protected]
Signed-off-by: Martin K. Petersen <[email protected]>
JIaxyga pushed a commit that referenced this pull request Sep 30, 2023
The following call trace shows a deadlock issue due to recursive locking of
mutex "device_mutex". First lock acquire is in target_for_each_device() and
second in target_free_device().

 PID: 148266   TASK: ffff8be21ffb5d00  CPU: 10   COMMAND: "iscsi_ttx"
  #0 [ffffa2bfc9ec3b18] __schedule at ffffffffa8060e7f
  #1 [ffffa2bfc9ec3ba0] schedule at ffffffffa8061224
  #2 [ffffa2bfc9ec3bb8] schedule_preempt_disabled at ffffffffa80615ee
  #3 [ffffa2bfc9ec3bc8] __mutex_lock at ffffffffa8062fd7
  #4 [ffffa2bfc9ec3c40] __mutex_lock_slowpath at ffffffffa80631d3
  #5 [ffffa2bfc9ec3c50] mutex_lock at ffffffffa806320c
  #6 [ffffa2bfc9ec3c68] target_free_device at ffffffffc0935998 [target_core_mod]
  #7 [ffffa2bfc9ec3c90] target_core_dev_release at ffffffffc092f975 [target_core_mod]
  #8 [ffffa2bfc9ec3ca0] config_item_put at ffffffffa79d250f
  #9 [ffffa2bfc9ec3cd0] config_item_put at ffffffffa79d2583
 #10 [ffffa2bfc9ec3ce0] target_devices_idr_iter at ffffffffc0933f3a [target_core_mod]
 #11 [ffffa2bfc9ec3d00] idr_for_each at ffffffffa803f6fc
 #12 [ffffa2bfc9ec3d60] target_for_each_device at ffffffffc0935670 [target_core_mod]
 #13 [ffffa2bfc9ec3d98] transport_deregister_session at ffffffffc0946408 [target_core_mod]
 #14 [ffffa2bfc9ec3dc8] iscsit_close_session at ffffffffc09a44a6 [iscsi_target_mod]
 #15 [ffffa2bfc9ec3df0] iscsit_close_connection at ffffffffc09a4a88 [iscsi_target_mod]
 #16 [ffffa2bfc9ec3df8] finish_task_switch at ffffffffa76e5d07
 #17 [ffffa2bfc9ec3e78] iscsit_take_action_for_connection_exit at ffffffffc0991c23 [iscsi_target_mod]
 #18 [ffffa2bfc9ec3ea0] iscsi_target_tx_thread at ffffffffc09a403b [iscsi_target_mod]
 #19 [ffffa2bfc9ec3f08] kthread at ffffffffa76d8080
 #20 [ffffa2bfc9ec3f50] ret_from_fork at ffffffffa8200364

Fixes: 36d4cb4 ("scsi: target: Avoid that EXTENDED COPY commands trigger lock inversion")
Signed-off-by: Junxiao Bi <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Mike Christie <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
JIaxyga pushed a commit that referenced this pull request Nov 22, 2023
Add test to validate BPF verifier's register range bounds tracking logic.

The main bulk is a lot of auto-generated tests based on a small set of
seed values for lower and upper 32 bits of full 64-bit values.
Currently we validate only range vs const comparisons, but the idea is
to start validating range over range comparisons in subsequent patch set.

When setting up initial register ranges we treat registers as one of
u64/s64/u32/s32 numeric types, and then independently perform conditional
comparisons based on a potentially different u64/s64/u32/s32 types. This
tests lots of tricky cases of deriving bounds information across
different numeric domains.

Given there are lots of auto-generated cases, we guard them behind
SLOW_TESTS=1 envvar requirement, and skip them altogether otherwise.
With current full set of upper/lower seed value, all supported
comparison operators and all the combinations of u64/s64/u32/s32 number
domains, we get about 7.7 million tests, which run in about 35 minutes
on my local qemu instance without parallelization. But we also split
those tests by init/cond numeric types, which allows to rely on
test_progs's parallelization of tests with `-j` option, getting run time
down to about 5 minutes on 8 cores. It's still something that shouldn't
be run during normal test_progs run.  But we can run it a reasonable
time, and so perhaps a nightly CI test run (once we have it) would be
a good option for this.

We also add a small set of tricky conditions that came up during
development and triggered various bugs or corner cases in either
selftest's reimplementation of range bounds logic or in verifier's logic
itself. These are fast enough to be run as part of normal test_progs
test run and are great for a quick sanity checking.

Let's take a look at test output to understand what's going on:

  $ sudo ./test_progs -t reg_bounds_crafted
  torvalds#191/1   reg_bounds_crafted/(u64)[0; 0xffffffff] (u64)< 0:OK
  ...
  torvalds#191/115 reg_bounds_crafted/(u64)[0; 0x17fffffff] (s32)< 0:OK
  ...
  torvalds#191/137 reg_bounds_crafted/(u64)[0xffffffff; 0x100000000] (u64)== 0:OK

Each test case is uniquely and fully described by this generated string.
E.g.: "(u64)[0; 0x17fffffff] (s32)< 0". This means that we
initialize a register (R6) in such a way that verifier knows that it can
have a value in [(u64)0; (u64)0x17fffffff] range. Another
register (R7) is also set up as u64, but this time a constant (zero in
this case). They then are compared using 32-bit signed < operation.
Resulting TRUE/FALSE branches are evaluated (including cases where it's
known that one of the branches will never be taken, in which case we
validate that verifier also determines this as a dead code). Test
validates that verifier's final register state matches expected state
based on selftest's own reg_state logic, implemented from scratch for
cross-checking purposes.

These test names can be conveniently used for further debugging, and if -vv
verboseness is requested we can get a corresponding verifier log (with
mark_precise logs filtered out as irrelevant and distracting). Example below is
slightly redacted for brevity, omitting irrelevant register output in
some places, marked with [...].

  $ sudo ./test_progs -a 'reg_bounds_crafted/(u32)[0; U32_MAX] (s32)< -1' -vv
  ...
  VERIFIER LOG:
  ========================
  func#0 @0
  0: R1=ctx(off=0,imm=0) R10=fp0
  0: (05) goto pc+2
  3: (85) call bpf_get_current_pid_tgid#14      ; R0_w=scalar()
  4: (bc) w6 = w0                       ; R0_w=scalar() R6_w=scalar(smin=0,smax=umax=4294967295,var_off=(0x0; 0xffffffff))
  5: (85) call bpf_get_current_pid_tgid#14      ; R0_w=scalar()
  6: (bc) w7 = w0                       ; R0_w=scalar() R7_w=scalar(smin=0,smax=umax=4294967295,var_off=(0x0; 0xffffffff))
  7: (b4) w1 = 0                        ; R1_w=0
  8: (b4) w2 = -1                       ; R2=4294967295
  9: (ae) if w6 < w1 goto pc-9
  9: R1=0 R6=scalar(smin=0,smax=umax=4294967295,var_off=(0x0; 0xffffffff))
  10: (2e) if w6 > w2 goto pc-10
  10: R2=4294967295 R6=scalar(smin=0,smax=umax=4294967295,var_off=(0x0; 0xffffffff))
  11: (b4) w1 = -1                      ; R1_w=4294967295
  12: (b4) w2 = -1                      ; R2_w=4294967295
  13: (ae) if w7 < w1 goto pc-13        ; R1_w=4294967295 R7=4294967295
  14: (2e) if w7 > w2 goto pc-14
  14: R2_w=4294967295 R7=4294967295
  15: (bc) w0 = w6                      ; [...] R6=scalar(id=1,smin=0,smax=umax=4294967295,var_off=(0x0; 0xffffffff))
  16: (bc) w0 = w7                      ; [...] R7=4294967295
  17: (ce) if w6 s< w7 goto pc+3        ; R6=scalar(id=1,smin=0,smax=umax=4294967295,smin32=-1,var_off=(0x0; 0xffffffff)) R7=4294967295
  18: (bc) w0 = w6                      ; [...] R6=scalar(id=1,smin=0,smax=umax=4294967295,smin32=-1,var_off=(0x0; 0xffffffff))
  19: (bc) w0 = w7                      ; [...] R7=4294967295
  20: (95) exit

  from 17 to 21: [...]
  21: (bc) w0 = w6                      ; [...] R6=scalar(id=1,smin=umin=umin32=2147483648,smax=umax=umax32=4294967294,smax32=-2,var_off=(0x80000000; 0x7fffffff))
  22: (bc) w0 = w7                      ; [...] R7=4294967295
  23: (95) exit

  from 13 to 1: [...]
  1: [...]
  1: (b7) r0 = 0                        ; R0_w=0
  2: (95) exit
  processed 24 insns (limit 1000000) max_states_per_insn 0 total_states 2 peak_states 2 mark_read 1
  =====================

Verifier log above is for `(u32)[0; U32_MAX] (s32)< -1` use cases, where u32
range is used for initialization, followed by signed < operator. Note
how we use w6/w7 in this case for register initialization (it would be
R6/R7 for 64-bit types) and then `if w6 s< w7` for comparison at
instruction #17. It will be `if R6 < R7` for 64-bit unsigned comparison.
Above example gives a good impression of the overall structure of a BPF
programs generated for reg_bounds tests.

In the future, this "framework" can be extended to test not just
conditional jumps, but also arithmetic operations. Adding randomized
testing is another possibility.

Some implementation notes. We basically have our own generics-like
operations on numbers, where all the numbers are stored in u64, but how
they are interpreted is passed as runtime argument enum num_t. Further,
`struct range` represents a bounds range, and those are collected
together into a minimal `struct reg_state`, which collects range bounds
across all four numberical domains: u64, s64, u32, s64.

Based on these primitives and `enum op` representing possible
conditional operation (<, <=, >, >=, ==, !=), there is a set of generic
helpers to perform "range arithmetics", which is used to maintain struct
reg_state. We simulate what verifier will do for reg bounds of R6 and R7
registers using these range and reg_state primitives. Simulated
information is used to determine branch taken conclusion and expected
exact register state across all four number domains.

Implementation of "range arithmetics" is more generic than what verifier
is currently performing: it allows range over range comparisons and
adjustments. This is the intended end goal of this patch set overall and verifier
logic is enhanced in subsequent patches in this series to handle range
vs range operations, at which point selftests are extended to validate
these conditions as well. For now it's range vs const cases only.

Note that tests are split into multiple groups by their numeric types
for initialization of ranges and for comparison operation. This allows
to use test_progs's -j parallelization to speed up tests, as we now have
16 groups of parallel running tests. Overall reduction of running time
that allows is pretty good, we go down from more than 30 minutes to
slightly less than 5 minutes running time.

Acked-by: Eduard Zingerman <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Acked-by: Shung-Hsi Yu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
JIaxyga pushed a commit that referenced this pull request Jan 4, 2024
When creating ceq_0 during probing irdma, cqp.sc_cqp will be sent as a
cqp_request to cqp->sc_cqp.sq_ring. If the request is pending when
removing the irdma driver or unplugging its aux device, cqp.sc_cqp will be
dereferenced as wrong struct in irdma_free_pending_cqp_request().

  PID: 3669   TASK: ffff88aef892c000  CPU: 28  COMMAND: "kworker/28:0"
   #0 [fffffe0000549e38] crash_nmi_callback at ffffffff810e3a34
   #1 [fffffe0000549e40] nmi_handle at ffffffff810788b2
   #2 [fffffe0000549ea0] default_do_nmi at ffffffff8107938f
   #3 [fffffe0000549eb8] do_nmi at ffffffff81079582
   #4 [fffffe0000549ef0] end_repeat_nmi at ffffffff82e016b4
      [exception RIP: native_queued_spin_lock_slowpath+1291]
      RIP: ffffffff8127e72b  RSP: ffff88aa841ef778  RFLAGS: 00000046
      RAX: 0000000000000000  RBX: ffff88b01f849700  RCX: ffffffff8127e47e
      RDX: 0000000000000000  RSI: 0000000000000004  RDI: ffffffff83857ec0
      RBP: ffff88afe3e4efc8   R8: ffffed15fc7c9dfa   R9: ffffed15fc7c9dfa
      R10: 0000000000000001  R11: ffffed15fc7c9df9  R12: 0000000000740000
      R13: ffff88b01f849708  R14: 0000000000000003  R15: ffffed1603f092e1
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0000
  -- <NMI exception stack> --
   #5 [ffff88aa841ef778] native_queued_spin_lock_slowpath at ffffffff8127e72b
   #6 [ffff88aa841ef7b0] _raw_spin_lock_irqsave at ffffffff82c22aa4
   #7 [ffff88aa841ef7c8] __wake_up_common_lock at ffffffff81257363
   #8 [ffff88aa841ef888] irdma_free_pending_cqp_request at ffffffffa0ba12cc [irdma]
   #9 [ffff88aa841ef958] irdma_cleanup_pending_cqp_op at ffffffffa0ba1469 [irdma]
   #10 [ffff88aa841ef9c0] irdma_ctrl_deinit_hw at ffffffffa0b2989f [irdma]
   #11 [ffff88aa841efa28] irdma_remove at ffffffffa0b252df [irdma]
   #12 [ffff88aa841efae8] auxiliary_bus_remove at ffffffff8219afdb
   #13 [ffff88aa841efb00] device_release_driver_internal at ffffffff821882e6
   #14 [ffff88aa841efb38] bus_remove_device at ffffffff82184278
   #15 [ffff88aa841efb88] device_del at ffffffff82179d23
   #16 [ffff88aa841efc48] ice_unplug_aux_dev at ffffffffa0eb1c14 [ice]
   #17 [ffff88aa841efc68] ice_service_task at ffffffffa0d88201 [ice]
   #18 [ffff88aa841efde8] process_one_work at ffffffff811c589a
   #19 [ffff88aa841efe60] worker_thread at ffffffff811c71ff
   #20 [ffff88aa841eff10] kthread at ffffffff811d87a0
   #21 [ffff88aa841eff50] ret_from_fork at ffffffff82e0022f

Fixes: 44d9e52 ("RDMA/irdma: Implement device initialization definitions")
Link: https://lore.kernel.org/r/[email protected]
Suggested-by: "Ismail, Mustafa" <[email protected]>
Signed-off-by: Shifeng Li <[email protected]>
Reviewed-by: Shiraz Saleem <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>
JIaxyga pushed a commit that referenced this pull request Mar 31, 2024
An errant disk backup on my desktop got into debugfs and triggered the
following deadlock scenario in the amdgpu debugfs files. The machine
also hard-resets immediately after those lines are printed (although I
wasn't able to reproduce that part when reading by hand):

[ 1318.016074][ T1082] ======================================================
[ 1318.016607][ T1082] WARNING: possible circular locking dependency detected
[ 1318.017107][ T1082] 6.8.0-rc7-00015-ge0c8221b72c0 #17 Not tainted
[ 1318.017598][ T1082] ------------------------------------------------------
[ 1318.018096][ T1082] tar/1082 is trying to acquire lock:
[ 1318.018585][ T1082] ffff98c44175d6a0 (&mm->mmap_lock){++++}-{3:3}, at: __might_fault+0x40/0x80
[ 1318.019084][ T1082]
[ 1318.019084][ T1082] but task is already holding lock:
[ 1318.020052][ T1082] ffff98c4c13f55f8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: amdgpu_debugfs_mqd_read+0x6a/0x250 [amdgpu]
[ 1318.020607][ T1082]
[ 1318.020607][ T1082] which lock already depends on the new lock.
[ 1318.020607][ T1082]
[ 1318.022081][ T1082]
[ 1318.022081][ T1082] the existing dependency chain (in reverse order) is:
[ 1318.023083][ T1082]
[ 1318.023083][ T1082] -> #2 (reservation_ww_class_mutex){+.+.}-{3:3}:
[ 1318.024114][ T1082]        __ww_mutex_lock.constprop.0+0xe0/0x12f0
[ 1318.024639][ T1082]        ww_mutex_lock+0x32/0x90
[ 1318.025161][ T1082]        dma_resv_lockdep+0x18a/0x330
[ 1318.025683][ T1082]        do_one_initcall+0x6a/0x350
[ 1318.026210][ T1082]        kernel_init_freeable+0x1a3/0x310
[ 1318.026728][ T1082]        kernel_init+0x15/0x1a0
[ 1318.027242][ T1082]        ret_from_fork+0x2c/0x40
[ 1318.027759][ T1082]        ret_from_fork_asm+0x11/0x20
[ 1318.028281][ T1082]
[ 1318.028281][ T1082] -> #1 (reservation_ww_class_acquire){+.+.}-{0:0}:
[ 1318.029297][ T1082]        dma_resv_lockdep+0x16c/0x330
[ 1318.029790][ T1082]        do_one_initcall+0x6a/0x350
[ 1318.030263][ T1082]        kernel_init_freeable+0x1a3/0x310
[ 1318.030722][ T1082]        kernel_init+0x15/0x1a0
[ 1318.031168][ T1082]        ret_from_fork+0x2c/0x40
[ 1318.031598][ T1082]        ret_from_fork_asm+0x11/0x20
[ 1318.032011][ T1082]
[ 1318.032011][ T1082] -> #0 (&mm->mmap_lock){++++}-{3:3}:
[ 1318.032778][ T1082]        __lock_acquire+0x14bf/0x2680
[ 1318.033141][ T1082]        lock_acquire+0xcd/0x2c0
[ 1318.033487][ T1082]        __might_fault+0x58/0x80
[ 1318.033814][ T1082]        amdgpu_debugfs_mqd_read+0x103/0x250 [amdgpu]
[ 1318.034181][ T1082]        full_proxy_read+0x55/0x80
[ 1318.034487][ T1082]        vfs_read+0xa7/0x360
[ 1318.034788][ T1082]        ksys_read+0x70/0xf0
[ 1318.035085][ T1082]        do_syscall_64+0x94/0x180
[ 1318.035375][ T1082]        entry_SYSCALL_64_after_hwframe+0x46/0x4e
[ 1318.035664][ T1082]
[ 1318.035664][ T1082] other info that might help us debug this:
[ 1318.035664][ T1082]
[ 1318.036487][ T1082] Chain exists of:
[ 1318.036487][ T1082]   &mm->mmap_lock --> reservation_ww_class_acquire --> reservation_ww_class_mutex
[ 1318.036487][ T1082]
[ 1318.037310][ T1082]  Possible unsafe locking scenario:
[ 1318.037310][ T1082]
[ 1318.037838][ T1082]        CPU0                    CPU1
[ 1318.038101][ T1082]        ----                    ----
[ 1318.038350][ T1082]   lock(reservation_ww_class_mutex);
[ 1318.038590][ T1082]                                lock(reservation_ww_class_acquire);
[ 1318.038839][ T1082]                                lock(reservation_ww_class_mutex);
[ 1318.039083][ T1082]   rlock(&mm->mmap_lock);
[ 1318.039328][ T1082]
[ 1318.039328][ T1082]  *** DEADLOCK ***
[ 1318.039328][ T1082]
[ 1318.040029][ T1082] 1 lock held by tar/1082:
[ 1318.040259][ T1082]  #0: ffff98c4c13f55f8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: amdgpu_debugfs_mqd_read+0x6a/0x250 [amdgpu]
[ 1318.040560][ T1082]
[ 1318.040560][ T1082] stack backtrace:
[ 1318.041053][ T1082] CPU: 22 PID: 1082 Comm: tar Not tainted 6.8.0-rc7-00015-ge0c8221b72c0 #17 3316c85d50e282c5643b075d1f01a4f6365e39c2
[ 1318.041329][ T1082] Hardware name: Gigabyte Technology Co., Ltd. B650 AORUS PRO AX/B650 AORUS PRO AX, BIOS F20 12/14/2023
[ 1318.041614][ T1082] Call Trace:
[ 1318.041895][ T1082]  <TASK>
[ 1318.042175][ T1082]  dump_stack_lvl+0x4a/0x80
[ 1318.042460][ T1082]  check_noncircular+0x145/0x160
[ 1318.042743][ T1082]  __lock_acquire+0x14bf/0x2680
[ 1318.043022][ T1082]  lock_acquire+0xcd/0x2c0
[ 1318.043301][ T1082]  ? __might_fault+0x40/0x80
[ 1318.043580][ T1082]  ? __might_fault+0x40/0x80
[ 1318.043856][ T1082]  __might_fault+0x58/0x80
[ 1318.044131][ T1082]  ? __might_fault+0x40/0x80
[ 1318.044408][ T1082]  amdgpu_debugfs_mqd_read+0x103/0x250 [amdgpu 8fe2afaa910cbd7654c8cab23563a94d6caebaab]
[ 1318.044749][ T1082]  full_proxy_read+0x55/0x80
[ 1318.045042][ T1082]  vfs_read+0xa7/0x360
[ 1318.045333][ T1082]  ksys_read+0x70/0xf0
[ 1318.045623][ T1082]  do_syscall_64+0x94/0x180
[ 1318.045913][ T1082]  ? do_syscall_64+0xa0/0x180
[ 1318.046201][ T1082]  ? lockdep_hardirqs_on+0x7d/0x100
[ 1318.046487][ T1082]  ? do_syscall_64+0xa0/0x180
[ 1318.046773][ T1082]  ? do_syscall_64+0xa0/0x180
[ 1318.047057][ T1082]  ? do_syscall_64+0xa0/0x180
[ 1318.047337][ T1082]  ? do_syscall_64+0xa0/0x180
[ 1318.047611][ T1082]  entry_SYSCALL_64_after_hwframe+0x46/0x4e
[ 1318.047887][ T1082] RIP: 0033:0x7f480b70a39d
[ 1318.048162][ T1082] Code: 91 ba 0d 00 f7 d8 64 89 02 b8 ff ff ff ff eb b2 e8 18 a3 01 00 0f 1f 84 00 00 00 00 00 80 3d a9 3c 0e 00 00 74 17 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 5b c3 66 2e 0f 1f 84 00 00 00 00 00 53 48 83
[ 1318.048769][ T1082] RSP: 002b:00007ffde77f5c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[ 1318.049083][ T1082] RAX: ffffffffffffffda RBX: 0000000000000800 RCX: 00007f480b70a39d
[ 1318.049392][ T1082] RDX: 0000000000000800 RSI: 000055c9f2120c00 RDI: 0000000000000008
[ 1318.049703][ T1082] RBP: 0000000000000800 R08: 000055c9f2120a94 R09: 0000000000000007
[ 1318.050011][ T1082] R10: 0000000000000000 R11: 0000000000000246 R12: 000055c9f2120c00
[ 1318.050324][ T1082] R13: 0000000000000008 R14: 0000000000000008 R15: 0000000000000800
[ 1318.050638][ T1082]  </TASK>

amdgpu_debugfs_mqd_read() holds a reservation when it calls
put_user(), which may fault and acquire the mmap_sem. This violates
the established locking order.

Bounce the mqd data through a kernel buffer to get put_user() out of
the illegal section.

Fixes: 445d85e ("drm/amdgpu: add debugfs interface for reading MQDs")
Cc: [email protected] # v6.5+
Reviewed-by: Shashank Sharma <[email protected]>
Signed-off-by: Johannes Weiner <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
JIaxyga pushed a commit that referenced this pull request Apr 7, 2024
commit 8678b10 upstream.

An errant disk backup on my desktop got into debugfs and triggered the
following deadlock scenario in the amdgpu debugfs files. The machine
also hard-resets immediately after those lines are printed (although I
wasn't able to reproduce that part when reading by hand):

[ 1318.016074][ T1082] ======================================================
[ 1318.016607][ T1082] WARNING: possible circular locking dependency detected
[ 1318.017107][ T1082] 6.8.0-rc7-00015-ge0c8221b72c0 #17 Not tainted
[ 1318.017598][ T1082] ------------------------------------------------------
[ 1318.018096][ T1082] tar/1082 is trying to acquire lock:
[ 1318.018585][ T1082] ffff98c44175d6a0 (&mm->mmap_lock){++++}-{3:3}, at: __might_fault+0x40/0x80
[ 1318.019084][ T1082]
[ 1318.019084][ T1082] but task is already holding lock:
[ 1318.020052][ T1082] ffff98c4c13f55f8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: amdgpu_debugfs_mqd_read+0x6a/0x250 [amdgpu]
[ 1318.020607][ T1082]
[ 1318.020607][ T1082] which lock already depends on the new lock.
[ 1318.020607][ T1082]
[ 1318.022081][ T1082]
[ 1318.022081][ T1082] the existing dependency chain (in reverse order) is:
[ 1318.023083][ T1082]
[ 1318.023083][ T1082] -> #2 (reservation_ww_class_mutex){+.+.}-{3:3}:
[ 1318.024114][ T1082]        __ww_mutex_lock.constprop.0+0xe0/0x12f0
[ 1318.024639][ T1082]        ww_mutex_lock+0x32/0x90
[ 1318.025161][ T1082]        dma_resv_lockdep+0x18a/0x330
[ 1318.025683][ T1082]        do_one_initcall+0x6a/0x350
[ 1318.026210][ T1082]        kernel_init_freeable+0x1a3/0x310
[ 1318.026728][ T1082]        kernel_init+0x15/0x1a0
[ 1318.027242][ T1082]        ret_from_fork+0x2c/0x40
[ 1318.027759][ T1082]        ret_from_fork_asm+0x11/0x20
[ 1318.028281][ T1082]
[ 1318.028281][ T1082] -> #1 (reservation_ww_class_acquire){+.+.}-{0:0}:
[ 1318.029297][ T1082]        dma_resv_lockdep+0x16c/0x330
[ 1318.029790][ T1082]        do_one_initcall+0x6a/0x350
[ 1318.030263][ T1082]        kernel_init_freeable+0x1a3/0x310
[ 1318.030722][ T1082]        kernel_init+0x15/0x1a0
[ 1318.031168][ T1082]        ret_from_fork+0x2c/0x40
[ 1318.031598][ T1082]        ret_from_fork_asm+0x11/0x20
[ 1318.032011][ T1082]
[ 1318.032011][ T1082] -> #0 (&mm->mmap_lock){++++}-{3:3}:
[ 1318.032778][ T1082]        __lock_acquire+0x14bf/0x2680
[ 1318.033141][ T1082]        lock_acquire+0xcd/0x2c0
[ 1318.033487][ T1082]        __might_fault+0x58/0x80
[ 1318.033814][ T1082]        amdgpu_debugfs_mqd_read+0x103/0x250 [amdgpu]
[ 1318.034181][ T1082]        full_proxy_read+0x55/0x80
[ 1318.034487][ T1082]        vfs_read+0xa7/0x360
[ 1318.034788][ T1082]        ksys_read+0x70/0xf0
[ 1318.035085][ T1082]        do_syscall_64+0x94/0x180
[ 1318.035375][ T1082]        entry_SYSCALL_64_after_hwframe+0x46/0x4e
[ 1318.035664][ T1082]
[ 1318.035664][ T1082] other info that might help us debug this:
[ 1318.035664][ T1082]
[ 1318.036487][ T1082] Chain exists of:
[ 1318.036487][ T1082]   &mm->mmap_lock --> reservation_ww_class_acquire --> reservation_ww_class_mutex
[ 1318.036487][ T1082]
[ 1318.037310][ T1082]  Possible unsafe locking scenario:
[ 1318.037310][ T1082]
[ 1318.037838][ T1082]        CPU0                    CPU1
[ 1318.038101][ T1082]        ----                    ----
[ 1318.038350][ T1082]   lock(reservation_ww_class_mutex);
[ 1318.038590][ T1082]                                lock(reservation_ww_class_acquire);
[ 1318.038839][ T1082]                                lock(reservation_ww_class_mutex);
[ 1318.039083][ T1082]   rlock(&mm->mmap_lock);
[ 1318.039328][ T1082]
[ 1318.039328][ T1082]  *** DEADLOCK ***
[ 1318.039328][ T1082]
[ 1318.040029][ T1082] 1 lock held by tar/1082:
[ 1318.040259][ T1082]  #0: ffff98c4c13f55f8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: amdgpu_debugfs_mqd_read+0x6a/0x250 [amdgpu]
[ 1318.040560][ T1082]
[ 1318.040560][ T1082] stack backtrace:
[ 1318.041053][ T1082] CPU: 22 PID: 1082 Comm: tar Not tainted 6.8.0-rc7-00015-ge0c8221b72c0 #17 3316c85d50e282c5643b075d1f01a4f6365e39c2
[ 1318.041329][ T1082] Hardware name: Gigabyte Technology Co., Ltd. B650 AORUS PRO AX/B650 AORUS PRO AX, BIOS F20 12/14/2023
[ 1318.041614][ T1082] Call Trace:
[ 1318.041895][ T1082]  <TASK>
[ 1318.042175][ T1082]  dump_stack_lvl+0x4a/0x80
[ 1318.042460][ T1082]  check_noncircular+0x145/0x160
[ 1318.042743][ T1082]  __lock_acquire+0x14bf/0x2680
[ 1318.043022][ T1082]  lock_acquire+0xcd/0x2c0
[ 1318.043301][ T1082]  ? __might_fault+0x40/0x80
[ 1318.043580][ T1082]  ? __might_fault+0x40/0x80
[ 1318.043856][ T1082]  __might_fault+0x58/0x80
[ 1318.044131][ T1082]  ? __might_fault+0x40/0x80
[ 1318.044408][ T1082]  amdgpu_debugfs_mqd_read+0x103/0x250 [amdgpu 8fe2afaa910cbd7654c8cab23563a94d6caebaab]
[ 1318.044749][ T1082]  full_proxy_read+0x55/0x80
[ 1318.045042][ T1082]  vfs_read+0xa7/0x360
[ 1318.045333][ T1082]  ksys_read+0x70/0xf0
[ 1318.045623][ T1082]  do_syscall_64+0x94/0x180
[ 1318.045913][ T1082]  ? do_syscall_64+0xa0/0x180
[ 1318.046201][ T1082]  ? lockdep_hardirqs_on+0x7d/0x100
[ 1318.046487][ T1082]  ? do_syscall_64+0xa0/0x180
[ 1318.046773][ T1082]  ? do_syscall_64+0xa0/0x180
[ 1318.047057][ T1082]  ? do_syscall_64+0xa0/0x180
[ 1318.047337][ T1082]  ? do_syscall_64+0xa0/0x180
[ 1318.047611][ T1082]  entry_SYSCALL_64_after_hwframe+0x46/0x4e
[ 1318.047887][ T1082] RIP: 0033:0x7f480b70a39d
[ 1318.048162][ T1082] Code: 91 ba 0d 00 f7 d8 64 89 02 b8 ff ff ff ff eb b2 e8 18 a3 01 00 0f 1f 84 00 00 00 00 00 80 3d a9 3c 0e 00 00 74 17 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 5b c3 66 2e 0f 1f 84 00 00 00 00 00 53 48 83
[ 1318.048769][ T1082] RSP: 002b:00007ffde77f5c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[ 1318.049083][ T1082] RAX: ffffffffffffffda RBX: 0000000000000800 RCX: 00007f480b70a39d
[ 1318.049392][ T1082] RDX: 0000000000000800 RSI: 000055c9f2120c00 RDI: 0000000000000008
[ 1318.049703][ T1082] RBP: 0000000000000800 R08: 000055c9f2120a94 R09: 0000000000000007
[ 1318.050011][ T1082] R10: 0000000000000000 R11: 0000000000000246 R12: 000055c9f2120c00
[ 1318.050324][ T1082] R13: 0000000000000008 R14: 0000000000000008 R15: 0000000000000800
[ 1318.050638][ T1082]  </TASK>

amdgpu_debugfs_mqd_read() holds a reservation when it calls
put_user(), which may fault and acquire the mmap_sem. This violates
the established locking order.

Bounce the mqd data through a kernel buffer to get put_user() out of
the illegal section.

Fixes: 445d85e ("drm/amdgpu: add debugfs interface for reading MQDs")
Cc: [email protected] # v6.5+
Reviewed-by: Shashank Sharma <[email protected]>
Signed-off-by: Johannes Weiner <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
JIaxyga pushed a commit that referenced this pull request Jun 19, 2024
The code in ocfs2_dio_end_io_write() estimates number of necessary
transaction credits using ocfs2_calc_extend_credits().  This however does
not take into account that the IO could be arbitrarily large and can
contain arbitrary number of extents.

Extent tree manipulations do often extend the current transaction but not
in all of the cases.  For example if we have only single block extents in
the tree, ocfs2_mark_extent_written() will end up calling
ocfs2_replace_extent_rec() all the time and we will never extend the
current transaction and eventually exhaust all the transaction credits if
the IO contains many single block extents.  Once that happens a
WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in
jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to
this error.  This was actually triggered by one of our customers on a
heavily fragmented OCFS2 filesystem.

To fix the issue make sure the transaction always has enough credits for
one extent insert before each call of ocfs2_mark_extent_written().

Heming Zhao said:

------
PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error"

PID: xxx  TASK: xxxx  CPU: 5  COMMAND: "SubmitThread-CA"
  #0 machine_kexec at ffffffff8c069932
  #1 __crash_kexec at ffffffff8c1338fa
  #2 panic at ffffffff8c1d69b9
  #3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2]
  #4 __ocfs2_abort at ffffffffc0c88387 [ocfs2]
  #5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2]
  #6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2]
  #7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2]
  #8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2]
  #9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2]
#10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2]
#11 dio_complete at ffffffff8c2b9fa7
#12 do_blockdev_direct_IO at ffffffff8c2bc09f
#13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2]
#14 generic_file_direct_write at ffffffff8c1dcf14
#15 __generic_file_write_iter at ffffffff8c1dd07b
#16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2]
#17 aio_write at ffffffff8c2cc72e
#18 kmem_cache_alloc at ffffffff8c248dde
#19 do_io_submit at ffffffff8c2ccada
#20 do_syscall_64 at ffffffff8c004984
#21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Fixes: c15471f ("ocfs2: fix sparse file & data ordering issue in direct io")
Signed-off-by: Jan Kara <[email protected]>
Reviewed-by: Joseph Qi <[email protected]>
Reviewed-by: Heming Zhao <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Junxiao Bi <[email protected]>
Cc: Changwei Ge <[email protected]>
Cc: Gang He <[email protected]>
Cc: Jun Piao <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
JIaxyga pushed a commit that referenced this pull request Aug 11, 2024
iter_finish_branch_entry() doesn't put the branch_info from/to map
elements creating memory leaks. This can be seen with:

```
$ perf record -e cycles -b perf test -w noploop
$ perf report -D
...
Direct leak of 984344 byte(s) in 123043 object(s) allocated from:
    #0 0x7fb2654f3bd7 in malloc libsanitizer/asan/asan_malloc_linux.cpp:69
    #1 0x564d3400d10b in map__get util/map.h:186
    #2 0x564d3400d10b in ip__resolve_ams util/machine.c:1981
    #3 0x564d34014d81 in sample__resolve_bstack util/machine.c:2151
    #4 0x564d34094790 in iter_prepare_branch_entry util/hist.c:898
    #5 0x564d34098fa4 in hist_entry_iter__add util/hist.c:1238
    #6 0x564d33d1f0c7 in process_sample_event tools/perf/builtin-report.c:334
    #7 0x564d34031eb7 in perf_session__deliver_event util/session.c:1655
    #8 0x564d3403ba52 in do_flush util/ordered-events.c:245
    #9 0x564d3403ba52 in __ordered_events__flush util/ordered-events.c:324
    #10 0x564d3402d32e in perf_session__process_user_event util/session.c:1708
    #11 0x564d34032480 in perf_session__process_event util/session.c:1877
    #12 0x564d340336ad in reader__read_event util/session.c:2399
    #13 0x564d34033fdc in reader__process_events util/session.c:2448
    #14 0x564d34033fdc in __perf_session__process_events util/session.c:2495
    #15 0x564d34033fdc in perf_session__process_events util/session.c:2661
    #16 0x564d33d27113 in __cmd_report tools/perf/builtin-report.c:1065
    #17 0x564d33d27113 in cmd_report tools/perf/builtin-report.c:1805
    #18 0x564d33e0ccb7 in run_builtin tools/perf/perf.c:350
    #19 0x564d33e0d45e in handle_internal_command tools/perf/perf.c:403
    #20 0x564d33cdd827 in run_argv tools/perf/perf.c:447
    #21 0x564d33cdd827 in main tools/perf/perf.c:561
...
```

Clearing up the map_symbols properly creates maps reference count
issues so resolve those. Resolving this issue doesn't improve peak
heap consumption for the test above.

Committer testing:

  $ sudo dnf install libasan
  $ make -k CORESIGHT=1 EXTRA_CFLAGS="-fsanitize=address" CC=clang O=/tmp/build/$(basename $PWD)/ -C tools/perf install-bin

Reviewed-by: Kan Liang <[email protected]>
Signed-off-by: Ian Rogers <[email protected]>
Tested-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Sun Haiyong <[email protected]>
Cc: Yanteng Si <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
JIaxyga pushed a commit that referenced this pull request Sep 15, 2024
A sysfs reader can race with a device reset or removal, attempting to
read device state when the device is not actually present. eg:

     [exception RIP: qed_get_current_link+17]
  #8 [ffffb9e4f2907c48] qede_get_link_ksettings at ffffffffc07a994a [qede]
  #9 [ffffb9e4f2907cd8] __rh_call_get_link_ksettings at ffffffff992b01a3
 #10 [ffffb9e4f2907d38] __ethtool_get_link_ksettings at ffffffff992b04e4
 #11 [ffffb9e4f2907d90] duplex_show at ffffffff99260300
 #12 [ffffb9e4f2907e38] dev_attr_show at ffffffff9905a01c
 #13 [ffffb9e4f2907e50] sysfs_kf_seq_show at ffffffff98e0145b
 #14 [ffffb9e4f2907e68] seq_read at ffffffff98d902e3
 #15 [ffffb9e4f2907ec8] vfs_read at ffffffff98d657d1
 #16 [ffffb9e4f2907f00] ksys_read at ffffffff98d65c3f
 #17 [ffffb9e4f2907f38] do_syscall_64 at ffffffff98a052fb

 crash> struct net_device.state ffff9a9d21336000
    state = 5,

state 5 is __LINK_STATE_START (0b1) and __LINK_STATE_NOCARRIER (0b100).
The device is not present, note lack of __LINK_STATE_PRESENT (0b10).

This is the same sort of panic as observed in commit 4224cfd
("net-sysfs: add check for netdevice being present to speed_show").

There are many other callers of __ethtool_get_link_ksettings() which
don't have a device presence check.

Move this check into ethtool to protect all callers.

Fixes: d519e17 ("net: export device speed and duplex via sysfs")
Fixes: 4224cfd ("net-sysfs: add check for netdevice being present to speed_show")
Signed-off-by: Jamie Bainbridge <[email protected]>
Link: https://patch.msgid.link/8bae218864beaa44ed01628140475b9bf641c5b0.1724393671.git.jamie.bainbridge@gmail.com
Signed-off-by: Jakub Kicinski <[email protected]>
JIaxyga pushed a commit that referenced this pull request Oct 16, 2024
The workqueue should be destroyed in mtk_jpeg_core.c since commit
09aea13 ("media: mtk-jpeg: refactor some variables"), otherwise
the below calltrace can be easily triggered.

[  677.862514] Unable to handle kernel paging request at virtual address dfff800000000023
[  677.863633] KASAN: null-ptr-deref in range [0x0000000000000118-0x000000000000011f]
...
[  677.879654] CPU: 6 PID: 1071 Comm: modprobe Tainted: G           O       6.8.12-mtk+gfa1a78e5d24b+ #17
...
[  677.882838] pc : destroy_workqueue+0x3c/0x770
[  677.883413] lr : mtk_jpegdec_destroy_workqueue+0x70/0x88 [mtk_jpeg_dec_hw]
[  677.884314] sp : ffff80008ad974f0
[  677.884744] x29: ffff80008ad974f0 x28: ffff0000d7115580 x27: ffff0000dd691070
[  677.885669] x26: ffff0000dd691408 x25: ffff8000844af3e0 x24: ffff80008ad97690
[  677.886592] x23: ffff0000e051d400 x22: ffff0000dd691010 x21: dfff800000000000
[  677.887515] x20: 0000000000000000 x19: 0000000000000000 x18: ffff800085397ac0
[  677.888438] x17: 0000000000000000 x16: ffff8000801b87c8 x15: 1ffff000115b2e10
[  677.889361] x14: 00000000f1f1f1f1 x13: 0000000000000000 x12: ffff7000115b2e4d
[  677.890285] x11: 1ffff000115b2e4c x10: ffff7000115b2e4c x9 : ffff80000aa43e90
[  677.891208] x8 : 00008fffeea4d1b4 x7 : ffff80008ad97267 x6 : 0000000000000001
[  677.892131] x5 : ffff80008ad97260 x4 : ffff7000115b2e4d x3 : 0000000000000000
[  677.893054] x2 : 0000000000000023 x1 : dfff800000000000 x0 : 0000000000000118
[  677.893977] Call trace:
[  677.894297]  destroy_workqueue+0x3c/0x770
[  677.894826]  mtk_jpegdec_destroy_workqueue+0x70/0x88 [mtk_jpeg_dec_hw]
[  677.895677]  devm_action_release+0x50/0x90
[  677.896211]  release_nodes+0xe8/0x170
[  677.896688]  devres_release_all+0xf8/0x178
[  677.897219]  device_unbind_cleanup+0x24/0x170
[  677.897785]  device_release_driver_internal+0x35c/0x480
[  677.898461]  device_release_driver+0x20/0x38
...
[  677.912665] ---[ end trace 0000000000000000 ]---

Fixes: 09aea13 ("media: mtk-jpeg: refactor some variables")
Cc: <[email protected]>
Signed-off-by: Guoqing Jiang <[email protected]>
Signed-off-by: Hans Verkuil <[email protected]>
JIaxyga pushed a commit that referenced this pull request Oct 16, 2024
In binder_add_freeze_work() we iterate over the proc->nodes with the
proc->inner_lock held. However, this lock is temporarily dropped in
order to acquire the node->lock first (lock nesting order). This can
race with binder_node_release() and trigger a use-after-free:

  ==================================================================
  BUG: KASAN: slab-use-after-free in _raw_spin_lock+0xe4/0x19c
  Write of size 4 at addr ffff53c04c29dd04 by task freeze/640

  CPU: 5 UID: 0 PID: 640 Comm: freeze Not tainted 6.11.0-07343-ga727812a8d45 #17
  Hardware name: linux,dummy-virt (DT)
  Call trace:
   _raw_spin_lock+0xe4/0x19c
   binder_add_freeze_work+0x148/0x478
   binder_ioctl+0x1e70/0x25ac
   __arm64_sys_ioctl+0x124/0x190

  Allocated by task 637:
   __kmalloc_cache_noprof+0x12c/0x27c
   binder_new_node+0x50/0x700
   binder_transaction+0x35ac/0x6f74
   binder_thread_write+0xfb8/0x42a0
   binder_ioctl+0x18f0/0x25ac
   __arm64_sys_ioctl+0x124/0x190

  Freed by task 637:
   kfree+0xf0/0x330
   binder_thread_read+0x1e88/0x3a68
   binder_ioctl+0x16d8/0x25ac
   __arm64_sys_ioctl+0x124/0x190
  ==================================================================

Fix the race by taking a temporary reference on the node before
releasing the proc->inner lock. This ensures the node remains alive
while in use.

Fixes: d579b04 ("binder: frozen notification")
Cc: [email protected]
Reviewed-by: Alice Ryhl <[email protected]>
Acked-by: Todd Kjos <[email protected]>
Signed-off-by: Carlos Llamas <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Gelbpunkt pushed a commit that referenced this pull request Feb 5, 2025
commit d62b04f upstream.

Haowei Yan <[email protected]> found that ets_class_from_arg() can
index an Out-Of-Bound class in ets_class_from_arg() when passed clid of
0. The overflow may cause local privilege escalation.

 [   18.852298] ------------[ cut here ]------------
 [   18.853271] UBSAN: array-index-out-of-bounds in net/sched/sch_ets.c:93:20
 [   18.853743] index 18446744073709551615 is out of range for type 'ets_class [16]'
 [   18.854254] CPU: 0 UID: 0 PID: 1275 Comm: poc Not tainted 6.12.6-dirty #17
 [   18.854821] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
 [   18.856532] Call Trace:
 [   18.857441]  <TASK>
 [   18.858227]  dump_stack_lvl+0xc2/0xf0
 [   18.859607]  dump_stack+0x10/0x20
 [   18.860908]  __ubsan_handle_out_of_bounds+0xa7/0xf0
 [   18.864022]  ets_class_change+0x3d6/0x3f0
 [   18.864322]  tc_ctl_tclass+0x251/0x910
 [   18.864587]  ? lock_acquire+0x5e/0x140
 [   18.865113]  ? __mutex_lock+0x9c/0xe70
 [   18.866009]  ? __mutex_lock+0xa34/0xe70
 [   18.866401]  rtnetlink_rcv_msg+0x170/0x6f0
 [   18.866806]  ? __lock_acquire+0x578/0xc10
 [   18.867184]  ? __pfx_rtnetlink_rcv_msg+0x10/0x10
 [   18.867503]  netlink_rcv_skb+0x59/0x110
 [   18.867776]  rtnetlink_rcv+0x15/0x30
 [   18.868159]  netlink_unicast+0x1c3/0x2b0
 [   18.868440]  netlink_sendmsg+0x239/0x4b0
 [   18.868721]  ____sys_sendmsg+0x3e2/0x410
 [   18.869012]  ___sys_sendmsg+0x88/0xe0
 [   18.869276]  ? rseq_ip_fixup+0x198/0x260
 [   18.869563]  ? rseq_update_cpu_node_id+0x10a/0x190
 [   18.869900]  ? trace_hardirqs_off+0x5a/0xd0
 [   18.870196]  ? syscall_exit_to_user_mode+0xcc/0x220
 [   18.870547]  ? do_syscall_64+0x93/0x150
 [   18.870821]  ? __memcg_slab_free_hook+0x69/0x290
 [   18.871157]  __sys_sendmsg+0x69/0xd0
 [   18.871416]  __x64_sys_sendmsg+0x1d/0x30
 [   18.871699]  x64_sys_call+0x9e2/0x2670
 [   18.871979]  do_syscall_64+0x87/0x150
 [   18.873280]  ? do_syscall_64+0x93/0x150
 [   18.874742]  ? lock_release+0x7b/0x160
 [   18.876157]  ? do_user_addr_fault+0x5ce/0x8f0
 [   18.877833]  ? irqentry_exit_to_user_mode+0xc2/0x210
 [   18.879608]  ? irqentry_exit+0x77/0xb0
 [   18.879808]  ? clear_bhb_loop+0x15/0x70
 [   18.880023]  ? clear_bhb_loop+0x15/0x70
 [   18.880223]  ? clear_bhb_loop+0x15/0x70
 [   18.880426]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
 [   18.880683] RIP: 0033:0x44a957
 [   18.880851] Code: ff ff e8 fc 00 00 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 8974 24 10
 [   18.881766] RSP: 002b:00007ffcdd00fad8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
 [   18.882149] RAX: ffffffffffffffda RBX: 00007ffcdd010db8 RCX: 000000000044a957
 [   18.882507] RDX: 0000000000000000 RSI: 00007ffcdd00fb70 RDI: 0000000000000003
 [   18.885037] RBP: 00007ffcdd010bc0 R08: 000000000703c770 R09: 000000000703c7c0
 [   18.887203] R10: 0000000000000080 R11: 0000000000000246 R12: 0000000000000001
 [   18.888026] R13: 00007ffcdd010da8 R14: 00000000004ca7d0 R15: 0000000000000001
 [   18.888395]  </TASK>
 [   18.888610] ---[ end trace ]---

Fixes: dcc68b4 ("net: sch_ets: Add a new Qdisc")
Reported-by: Haowei Yan <[email protected]>
Suggested-by: Haowei Yan <[email protected]>
Signed-off-by: Jamal Hadi Salim <[email protected]>
Reviewed-by: Eric Dumazet <[email protected]>
Reviewed-by: Petr Machata <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Gelbpunkt pushed a commit that referenced this pull request Feb 10, 2025
commit ee1b504 upstream.

The following kernel oops is thrown when trying to remove the max96712
module:

Unable to handle kernel paging request at virtual address 00007375746174db
Mem abort info:
  ESR = 0x0000000096000004
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x04: level 0 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
  CM = 0, WnR = 0, TnD = 0, TagAccess = 0
  GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
user pgtable: 4k pages, 48-bit VAs, pgdp=000000010af89000
[00007375746174db] pgd=0000000000000000, p4d=0000000000000000
Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
Modules linked in: crct10dif_ce polyval_ce mxc_jpeg_encdec flexcan
    snd_soc_fsl_sai snd_soc_fsl_asoc_card snd_soc_fsl_micfil dwc_mipi_csi2
    imx_csi_formatter polyval_generic v4l2_jpeg imx_pcm_dma can_dev
    snd_soc_imx_audmux snd_soc_wm8962 snd_soc_imx_card snd_soc_fsl_utils
    max96712(C-) rpmsg_ctrl rpmsg_char pwm_fan fuse
    [last unloaded: imx8_isi]
CPU: 0 UID: 0 PID: 754 Comm: rmmod
	    Tainted: G         C    6.12.0-rc6-06364-g327fec852c31 #17
Tainted: [C]=CRAP
Hardware name: NXP i.MX95 19X19 board (DT)
pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : led_put+0x1c/0x40
lr : v4l2_subdev_put_privacy_led+0x48/0x58
sp : ffff80008699bbb0
x29: ffff80008699bbb0 x28: ffff00008ac233c0 x27: 0000000000000000
x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000
x23: ffff000080cf1170 x22: ffff00008b53bd00 x21: ffff8000822ad1c8
x20: ffff000080ff5c00 x19: ffff00008b53be40 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
x14: 0000000000000004 x13: ffff0000800f8010 x12: 0000000000000000
x11: ffff000082acf5c0 x10: ffff000082acf478 x9 : ffff0000800f8010
x8 : 0101010101010101 x7 : 7f7f7f7f7f7f7f7f x6 : fefefeff6364626d
x5 : 8080808000000000 x4 : 0000000000000020 x3 : 00000000553a3dc1
x2 : ffff00008ac233c0 x1 : ffff00008ac233c0 x0 : ff00737574617473
Call trace:
 led_put+0x1c/0x40
 v4l2_subdev_put_privacy_led+0x48/0x58
 v4l2_async_unregister_subdev+0x2c/0x1a4
 max96712_remove+0x1c/0x38 [max96712]
 i2c_device_remove+0x2c/0x9c
 device_remove+0x4c/0x80
 device_release_driver_internal+0x1cc/0x228
 driver_detach+0x4c/0x98
 bus_remove_driver+0x6c/0xbc
 driver_unregister+0x30/0x60
 i2c_del_driver+0x54/0x64
 max96712_i2c_driver_exit+0x18/0x1d0 [max96712]
 __arm64_sys_delete_module+0x1a4/0x290
 invoke_syscall+0x48/0x10c
 el0_svc_common.constprop.0+0xc0/0xe0
 do_el0_svc+0x1c/0x28
 el0_svc+0x34/0xd8
 el0t_64_sync_handler+0x120/0x12c
 el0t_64_sync+0x190/0x194
Code: f9000bf3 aa0003f3 f9402800 f9402000 (f9403400)
---[ end trace 0000000000000000 ]---

This happens because in v4l2_i2c_subdev_init(), the i2c_set_cliendata()
is called again and the data is overwritten to point to sd, instead of
priv. So, in remove(), the wrong pointer is passed to
v4l2_async_unregister_subdev(), leading to a crash.

Fixes: 5814f32 ("media: staging: max96712: Add basic support for MAX96712 GMSL2 deserializer")
Signed-off-by: Laurentiu Palcu <[email protected]>
Cc: [email protected]
Reviewed-by: Niklas Söderlund <[email protected]>
Reviewed-by: Ricardo Ribalda <[email protected]>
Signed-off-by: Sakari Ailus <[email protected]>
Signed-off-by: Mauro Carvalho Chehab <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Gelbpunkt pushed a commit that referenced this pull request Feb 13, 2025
…O write

After commit ac325fc ("btrfs: do not hold the extent lock for entire
read") we can now trigger a race between a task doing a direct IO write
and readahead. When this race is triggered it results in tasks getting
stale data when they attempt do a buffered read (including the task that
did the direct IO write).

This race can be sporadically triggered with test case generic/418, failing
like this:

   $ ./check generic/418
   FSTYP         -- btrfs
   PLATFORM      -- Linux/x86_64 debian0 6.13.0-rc7-btrfs-next-185+ #17 SMP PREEMPT_DYNAMIC Mon Feb  3 12:28:46 WET 2025
   MKFS_OPTIONS  -- /dev/sdc
   MOUNT_OPTIONS -- /dev/sdc /home/fdmanana/btrfs-tests/scratch_1

   generic/418 14s ... - output mismatch (see /home/fdmanana/git/hub/xfstests/results//generic/418.out.bad)
       --- tests/generic/418.out	2020-06-10 19:29:03.850519863 +0100
       +++ /home/fdmanana/git/hub/xfstests/results//generic/418.out.bad	2025-02-03 15:42:36.974609476 +0000
       @@ -1,2 +1,5 @@
        QA output created by 418
       +cmpbuf: offset 0: Expected: 0x1, got 0x0
       +[6:0] FAIL - comparison failed, offset 24576
       +diotest -wp -b 4096 -n 8 -i 4 failed at loop 3
        Silence is golden
       ...
       (Run 'diff -u /home/fdmanana/git/hub/xfstests/tests/generic/418.out /home/fdmanana/git/hub/xfstests/results//generic/418.out.bad'  to see the entire diff)
   Ran: generic/418
   Failures: generic/418
   Failed 1 of 1 tests

The race happens like this:

1) A file has a prealloc extent for the range [16K, 28K);

2) Task A starts a direct IO write against file range [24K, 28K).
   At the start of the direct IO write it invalidates the page cache at
   __iomap_dio_rw() with kiocb_invalidate_pages() for the 4K page at file
   offset 24K;

3) Task A enters btrfs_dio_iomap_begin() and locks the extent range
   [24K, 28K);

4) Task B starts a readahead for file range [16K, 28K), entering
   btrfs_readahead().

   First it attempts to read the page at offset 16K by entering
   btrfs_do_readpage(), where it calls get_extent_map(), locks the range
   [16K, 20K) and gets the extent map for the range [16K, 28K), caching
   it into the 'em_cached' variable declared in the local stack of
   btrfs_readahead(), and then unlocks the range [16K, 20K).

   Since the extent map has the prealloc flag, at btrfs_do_readpage() we
   zero out the page's content and don't submit any bio to read the page
   from the extent.

   Then it attempts to read the page at offset 20K entering
   btrfs_do_readpage() where we reuse the previously cached extent map
   (decided by get_extent_map()) since it spans the page's range and
   it's still in the inode's extent map tree.

   Just like for the previous page, we zero out the page's content since
   the extent map has the prealloc flag set.

   Then it attempts to read the page at offset 24K entering
   btrfs_do_readpage() where we reuse the previously cached extent map
   (decided by get_extent_map()) since it spans the page's range and
   it's still in the inode's extent map tree.

   Just like for the previous pages, we zero out the page's content since
   the extent map has the prealloc flag set. Note that we didn't lock the
   extent range [24K, 28K), so we didn't synchronize with the ongoing
   direct IO write being performed by task A;

5) Task A enters btrfs_create_dio_extent() and creates an ordered extent
   for the range [24K, 28K), with the flags BTRFS_ORDERED_DIRECT and
   BTRFS_ORDERED_PREALLOC set;

6) Task A unlocks the range [24K, 28K) at btrfs_dio_iomap_begin();

7) The ordered extent enters btrfs_finish_one_ordered() and locks the
   range [24K, 28K);

8) Task A enters fs/iomap/direct-io.c:iomap_dio_complete() and it tries
   to invalidate the page at offset 24K by calling
   kiocb_invalidate_post_direct_write(), resulting in a call chain that
   ends up at btrfs_release_folio().

   The btrfs_release_folio() call ends up returning false because the range
   for the page at file offset 24K is currently locked by the task doing
   the ordered extent completion in the previous step (7), so we have:

   btrfs_release_folio() ->
      __btrfs_release_folio() ->
         try_release_extent_mapping() ->
	     try_release_extent_state()

   This last function checking that the range is locked and returning false
   and propagating it up to btrfs_release_folio().

   So this results in a failure to invalidate the page and
   kiocb_invalidate_post_direct_write() triggers this message logged in
   dmesg:

     Page cache invalidation failure on direct I/O.  Possible data corruption due to collision with buffered I/O!

   After this we leave the page cache with stale data for the file range
   [24K, 28K), filled with zeroes instead of the data written by direct IO
   write (all bytes with a 0x01 value), so any task attempting to read with
   buffered IO, including the task that did the direct IO write, will get
   all bytes in the range with a 0x00 value instead of the written data.

Fix this by locking the range, with btrfs_lock_and_flush_ordered_range(),
at the two callers of btrfs_do_readpage() instead of doing it at
get_extent_map(), just like we did before commit ac325fc ("btrfs: do
not hold the extent lock for entire read"), and unlocking the range after
all the calls to btrfs_do_readpage(). This way we never reuse a cached
extent map without flushing any pending ordered extents from a concurrent
direct IO write.

Fixes: ac325fc ("btrfs: do not hold the extent lock for entire read")
Reviewed-by: Qu Wenruo <[email protected]>
Signed-off-by: Filipe Manana <[email protected]>
Signed-off-by: David Sterba <[email protected]>
Gelbpunkt pushed a commit that referenced this pull request Feb 13, 2025
At btrfs_write_check() if our file's i_size is not sector size aligned and
we have a write that starts at an offset larger than the i_size that falls
within the same page of the i_size, then we end up not zeroing the file
range [i_size, write_offset).

The code is this:

    start_pos = round_down(pos, fs_info->sectorsize);
    oldsize = i_size_read(inode);
    if (start_pos > oldsize) {
        /* Expand hole size to cover write data, preventing empty gap */
        loff_t end_pos = round_up(pos + count, fs_info->sectorsize);

        ret = btrfs_cont_expand(BTRFS_I(inode), oldsize, end_pos);
        if (ret)
            return ret;
    }

So if our file's i_size is 90269 bytes and a write at offset 90365 bytes
comes in, we get 'start_pos' set to 90112 bytes, which is less than the
i_size and therefore we don't zero out the range [90269, 90365) by
calling btrfs_cont_expand().

This is an old bug introduced in commit 9036c10 ("Btrfs: update hole
handling v2"), from 2008, and the buggy code got moved around over the
years.

Fix this by discarding 'start_pos' and comparing against the write offset
('pos') without any alignment.

This bug was recently exposed by test case generic/363 which tests this
scenario by polluting ranges beyond eof with a mmap write and than verify
that after a file increases we get zeroes for the range which is supposed
to be a hole and not what we wrote with the previous mmaped write.

We're only seeing this exposed now because generic/363 used to run only
on xfs until last Sunday's fstests update.

The test was failing like this:

   $ ./check generic/363
   FSTYP         -- btrfs
   PLATFORM      -- Linux/x86_64 debian0 6.13.0-rc7-btrfs-next-185+ #17 SMP PREEMPT_DYNAMIC Mon Feb  3 12:28:46 WET 2025
   MKFS_OPTIONS  -- /dev/sdc
   MOUNT_OPTIONS -- /dev/sdc /home/fdmanana/btrfs-tests/scratch_1

   generic/363 0s ... [failed, exit status 1]- output mismatch (see /home/fdmanana/git/hub/xfstests/results//generic/363.out.bad)
       --- tests/generic/363.out	2025-02-05 15:31:14.013646509 +0000
       +++ /home/fdmanana/git/hub/xfstests/results//generic/363.out.bad	2025-02-05 17:25:33.112630781 +0000
       @@ -1 +1,46 @@
        QA output created by 363
       +READ BAD DATA: offset = 0xdcad, size = 0xd921, fname = /home/fdmanana/btrfs-tests/dev/junk
       +OFFSET      GOOD    BAD     RANGE
       +0x1609d     0x0000  0x3104  0x0
       +operation# (mod 256) for the bad data may be 4
       +0x1609e     0x0000  0x0472  0x1
       +operation# (mod 256) for the bad data may be 4
       ...
       (Run 'diff -u /home/fdmanana/git/hub/xfstests/tests/generic/363.out /home/fdmanana/git/hub/xfstests/results//generic/363.out.bad'  to see the entire diff)
   Ran: generic/363
   Failures: generic/363
   Failed 1 of 1 tests

Reviewed-by: Qu Wenruo <[email protected]>
Signed-off-by: Filipe Manana <[email protected]>
Signed-off-by: David Sterba <[email protected]>
Gelbpunkt pushed a commit that referenced this pull request Feb 13, 2025
…O write

After commit ac325fc ("btrfs: do not hold the extent lock for entire
read") we can now trigger a race between a task doing a direct IO write
and readahead. When this race is triggered it results in tasks getting
stale data when they attempt do a buffered read (including the task that
did the direct IO write).

This race can be sporadically triggered with test case generic/418, failing
like this:

   $ ./check generic/418
   FSTYP         -- btrfs
   PLATFORM      -- Linux/x86_64 debian0 6.13.0-rc7-btrfs-next-185+ #17 SMP PREEMPT_DYNAMIC Mon Feb  3 12:28:46 WET 2025
   MKFS_OPTIONS  -- /dev/sdc
   MOUNT_OPTIONS -- /dev/sdc /home/fdmanana/btrfs-tests/scratch_1

   generic/418 14s ... - output mismatch (see /home/fdmanana/git/hub/xfstests/results//generic/418.out.bad)
       --- tests/generic/418.out	2020-06-10 19:29:03.850519863 +0100
       +++ /home/fdmanana/git/hub/xfstests/results//generic/418.out.bad	2025-02-03 15:42:36.974609476 +0000
       @@ -1,2 +1,5 @@
        QA output created by 418
       +cmpbuf: offset 0: Expected: 0x1, got 0x0
       +[6:0] FAIL - comparison failed, offset 24576
       +diotest -wp -b 4096 -n 8 -i 4 failed at loop 3
        Silence is golden
       ...
       (Run 'diff -u /home/fdmanana/git/hub/xfstests/tests/generic/418.out /home/fdmanana/git/hub/xfstests/results//generic/418.out.bad'  to see the entire diff)
   Ran: generic/418
   Failures: generic/418
   Failed 1 of 1 tests

The race happens like this:

1) A file has a prealloc extent for the range [16K, 28K);

2) Task A starts a direct IO write against file range [24K, 28K).
   At the start of the direct IO write it invalidates the page cache at
   __iomap_dio_rw() with kiocb_invalidate_pages() for the 4K page at file
   offset 24K;

3) Task A enters btrfs_dio_iomap_begin() and locks the extent range
   [24K, 28K);

4) Task B starts a readahead for file range [16K, 28K), entering
   btrfs_readahead().

   First it attempts to read the page at offset 16K by entering
   btrfs_do_readpage(), where it calls get_extent_map(), locks the range
   [16K, 20K) and gets the extent map for the range [16K, 28K), caching
   it into the 'em_cached' variable declared in the local stack of
   btrfs_readahead(), and then unlocks the range [16K, 20K).

   Since the extent map has the prealloc flag, at btrfs_do_readpage() we
   zero out the page's content and don't submit any bio to read the page
   from the extent.

   Then it attempts to read the page at offset 20K entering
   btrfs_do_readpage() where we reuse the previously cached extent map
   (decided by get_extent_map()) since it spans the page's range and
   it's still in the inode's extent map tree.

   Just like for the previous page, we zero out the page's content since
   the extent map has the prealloc flag set.

   Then it attempts to read the page at offset 24K entering
   btrfs_do_readpage() where we reuse the previously cached extent map
   (decided by get_extent_map()) since it spans the page's range and
   it's still in the inode's extent map tree.

   Just like for the previous pages, we zero out the page's content since
   the extent map has the prealloc flag set. Note that we didn't lock the
   extent range [24K, 28K), so we didn't synchronize with the ongoing
   direct IO write being performed by task A;

5) Task A enters btrfs_create_dio_extent() and creates an ordered extent
   for the range [24K, 28K), with the flags BTRFS_ORDERED_DIRECT and
   BTRFS_ORDERED_PREALLOC set;

6) Task A unlocks the range [24K, 28K) at btrfs_dio_iomap_begin();

7) The ordered extent enters btrfs_finish_one_ordered() and locks the
   range [24K, 28K);

8) Task A enters fs/iomap/direct-io.c:iomap_dio_complete() and it tries
   to invalidate the page at offset 24K by calling
   kiocb_invalidate_post_direct_write(), resulting in a call chain that
   ends up at btrfs_release_folio().

   The btrfs_release_folio() call ends up returning false because the range
   for the page at file offset 24K is currently locked by the task doing
   the ordered extent completion in the previous step (7), so we have:

   btrfs_release_folio() ->
      __btrfs_release_folio() ->
         try_release_extent_mapping() ->
	     try_release_extent_state()

   This last function checking that the range is locked and returning false
   and propagating it up to btrfs_release_folio().

   So this results in a failure to invalidate the page and
   kiocb_invalidate_post_direct_write() triggers this message logged in
   dmesg:

     Page cache invalidation failure on direct I/O.  Possible data corruption due to collision with buffered I/O!

   After this we leave the page cache with stale data for the file range
   [24K, 28K), filled with zeroes instead of the data written by direct IO
   write (all bytes with a 0x01 value), so any task attempting to read with
   buffered IO, including the task that did the direct IO write, will get
   all bytes in the range with a 0x00 value instead of the written data.

Fix this by locking the range, with btrfs_lock_and_flush_ordered_range(),
at the two callers of btrfs_do_readpage() instead of doing it at
get_extent_map(), just like we did before commit ac325fc ("btrfs: do
not hold the extent lock for entire read"), and unlocking the range after
all the calls to btrfs_do_readpage(). This way we never reuse a cached
extent map without flushing any pending ordered extents from a concurrent
direct IO write.

Fixes: ac325fc ("btrfs: do not hold the extent lock for entire read")
Reviewed-by: Qu Wenruo <[email protected]>
Signed-off-by: Filipe Manana <[email protected]>
Signed-off-by: David Sterba <[email protected]>
Gelbpunkt pushed a commit that referenced this pull request Feb 13, 2025
At btrfs_write_check() if our file's i_size is not sector size aligned and
we have a write that starts at an offset larger than the i_size that falls
within the same page of the i_size, then we end up not zeroing the file
range [i_size, write_offset).

The code is this:

    start_pos = round_down(pos, fs_info->sectorsize);
    oldsize = i_size_read(inode);
    if (start_pos > oldsize) {
        /* Expand hole size to cover write data, preventing empty gap */
        loff_t end_pos = round_up(pos + count, fs_info->sectorsize);

        ret = btrfs_cont_expand(BTRFS_I(inode), oldsize, end_pos);
        if (ret)
            return ret;
    }

So if our file's i_size is 90269 bytes and a write at offset 90365 bytes
comes in, we get 'start_pos' set to 90112 bytes, which is less than the
i_size and therefore we don't zero out the range [90269, 90365) by
calling btrfs_cont_expand().

This is an old bug introduced in commit 9036c10 ("Btrfs: update hole
handling v2"), from 2008, and the buggy code got moved around over the
years.

Fix this by discarding 'start_pos' and comparing against the write offset
('pos') without any alignment.

This bug was recently exposed by test case generic/363 which tests this
scenario by polluting ranges beyond EOF with an mmap write and than verify
that after a file increases we get zeroes for the range which is supposed
to be a hole and not what we wrote with the previous mmaped write.

We're only seeing this exposed now because generic/363 used to run only
on xfs until last Sunday's fstests update.

The test was failing like this:

   $ ./check generic/363
   FSTYP         -- btrfs
   PLATFORM      -- Linux/x86_64 debian0 6.13.0-rc7-btrfs-next-185+ #17 SMP PREEMPT_DYNAMIC Mon Feb  3 12:28:46 WET 2025
   MKFS_OPTIONS  -- /dev/sdc
   MOUNT_OPTIONS -- /dev/sdc /home/fdmanana/btrfs-tests/scratch_1

   generic/363 0s ... [failed, exit status 1]- output mismatch (see /home/fdmanana/git/hub/xfstests/results//generic/363.out.bad)
       --- tests/generic/363.out	2025-02-05 15:31:14.013646509 +0000
       +++ /home/fdmanana/git/hub/xfstests/results//generic/363.out.bad	2025-02-05 17:25:33.112630781 +0000
       @@ -1 +1,46 @@
        QA output created by 363
       +READ BAD DATA: offset = 0xdcad, size = 0xd921, fname = /home/fdmanana/btrfs-tests/dev/junk
       +OFFSET      GOOD    BAD     RANGE
       +0x1609d     0x0000  0x3104  0x0
       +operation# (mod 256) for the bad data may be 4
       +0x1609e     0x0000  0x0472  0x1
       +operation# (mod 256) for the bad data may be 4
       ...
       (Run 'diff -u /home/fdmanana/git/hub/xfstests/tests/generic/363.out /home/fdmanana/git/hub/xfstests/results//generic/363.out.bad'  to see the entire diff)
   Ran: generic/363
   Failures: generic/363
   Failed 1 of 1 tests

Fixes: 9036c10 ("Btrfs: update hole handling v2")
CC: [email protected]
Reviewed-by: Qu Wenruo <[email protected]>
Signed-off-by: Filipe Manana <[email protected]>
Signed-off-by: David Sterba <[email protected]>
Gelbpunkt pushed a commit that referenced this pull request Feb 23, 2025
commit da2dccd upstream.

At btrfs_write_check() if our file's i_size is not sector size aligned and
we have a write that starts at an offset larger than the i_size that falls
within the same page of the i_size, then we end up not zeroing the file
range [i_size, write_offset).

The code is this:

    start_pos = round_down(pos, fs_info->sectorsize);
    oldsize = i_size_read(inode);
    if (start_pos > oldsize) {
        /* Expand hole size to cover write data, preventing empty gap */
        loff_t end_pos = round_up(pos + count, fs_info->sectorsize);

        ret = btrfs_cont_expand(BTRFS_I(inode), oldsize, end_pos);
        if (ret)
            return ret;
    }

So if our file's i_size is 90269 bytes and a write at offset 90365 bytes
comes in, we get 'start_pos' set to 90112 bytes, which is less than the
i_size and therefore we don't zero out the range [90269, 90365) by
calling btrfs_cont_expand().

This is an old bug introduced in commit 9036c10 ("Btrfs: update hole
handling v2"), from 2008, and the buggy code got moved around over the
years.

Fix this by discarding 'start_pos' and comparing against the write offset
('pos') without any alignment.

This bug was recently exposed by test case generic/363 which tests this
scenario by polluting ranges beyond EOF with an mmap write and than verify
that after a file increases we get zeroes for the range which is supposed
to be a hole and not what we wrote with the previous mmaped write.

We're only seeing this exposed now because generic/363 used to run only
on xfs until last Sunday's fstests update.

The test was failing like this:

   $ ./check generic/363
   FSTYP         -- btrfs
   PLATFORM      -- Linux/x86_64 debian0 6.13.0-rc7-btrfs-next-185+ #17 SMP PREEMPT_DYNAMIC Mon Feb  3 12:28:46 WET 2025
   MKFS_OPTIONS  -- /dev/sdc
   MOUNT_OPTIONS -- /dev/sdc /home/fdmanana/btrfs-tests/scratch_1

   generic/363 0s ... [failed, exit status 1]- output mismatch (see /home/fdmanana/git/hub/xfstests/results//generic/363.out.bad)
#      --- tests/generic/363.out	2025-02-05 15:31:14.013646509 +0000
#      +++ /home/fdmanana/git/hub/xfstests/results//generic/363.out.bad	2025-02-05 17:25:33.112630781 +0000
       @@ -1 +1,46 @@
        QA output created by 363
       +READ BAD DATA: offset = 0xdcad, size = 0xd921, fname = /home/fdmanana/btrfs-tests/dev/junk
       +OFFSET      GOOD    BAD     RANGE
       +0x1609d     0x0000  0x3104  0x0
       +operation# (mod 256) for the bad data may be 4
       +0x1609e     0x0000  0x0472  0x1
       +operation# (mod 256) for the bad data may be 4
       ...
       (Run 'diff -u /home/fdmanana/git/hub/xfstests/tests/generic/363.out /home/fdmanana/git/hub/xfstests/results//generic/363.out.bad'  to see the entire diff)
   Ran: generic/363
   Failures: generic/363
   Failed 1 of 1 tests

Fixes: 9036c10 ("Btrfs: update hole handling v2")
CC: [email protected]
Reviewed-by: Qu Wenruo <[email protected]>
Signed-off-by: Filipe Manana <[email protected]>
Signed-off-by: David Sterba <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Gelbpunkt pushed a commit that referenced this pull request Feb 23, 2025
…O write

[ Upstream commit acc18e1 ]

After commit ac325fc ("btrfs: do not hold the extent lock for entire
read") we can now trigger a race between a task doing a direct IO write
and readahead. When this race is triggered it results in tasks getting
stale data when they attempt do a buffered read (including the task that
did the direct IO write).

This race can be sporadically triggered with test case generic/418, failing
like this:

   $ ./check generic/418
   FSTYP         -- btrfs
   PLATFORM      -- Linux/x86_64 debian0 6.13.0-rc7-btrfs-next-185+ #17 SMP PREEMPT_DYNAMIC Mon Feb  3 12:28:46 WET 2025
   MKFS_OPTIONS  -- /dev/sdc
   MOUNT_OPTIONS -- /dev/sdc /home/fdmanana/btrfs-tests/scratch_1

   generic/418 14s ... - output mismatch (see /home/fdmanana/git/hub/xfstests/results//generic/418.out.bad)
#      --- tests/generic/418.out	2020-06-10 19:29:03.850519863 +0100
#      +++ /home/fdmanana/git/hub/xfstests/results//generic/418.out.bad	2025-02-03 15:42:36.974609476 +0000
       @@ -1,2 +1,5 @@
        QA output created by 418
       +cmpbuf: offset 0: Expected: 0x1, got 0x0
       +[6:0] FAIL - comparison failed, offset 24576
       +diotest -wp -b 4096 -n 8 -i 4 failed at loop 3
        Silence is golden
       ...
       (Run 'diff -u /home/fdmanana/git/hub/xfstests/tests/generic/418.out /home/fdmanana/git/hub/xfstests/results//generic/418.out.bad'  to see the entire diff)
   Ran: generic/418
   Failures: generic/418
   Failed 1 of 1 tests

The race happens like this:

1) A file has a prealloc extent for the range [16K, 28K);

2) Task A starts a direct IO write against file range [24K, 28K).
   At the start of the direct IO write it invalidates the page cache at
   __iomap_dio_rw() with kiocb_invalidate_pages() for the 4K page at file
   offset 24K;

3) Task A enters btrfs_dio_iomap_begin() and locks the extent range
   [24K, 28K);

4) Task B starts a readahead for file range [16K, 28K), entering
   btrfs_readahead().

   First it attempts to read the page at offset 16K by entering
   btrfs_do_readpage(), where it calls get_extent_map(), locks the range
   [16K, 20K) and gets the extent map for the range [16K, 28K), caching
   it into the 'em_cached' variable declared in the local stack of
   btrfs_readahead(), and then unlocks the range [16K, 20K).

   Since the extent map has the prealloc flag, at btrfs_do_readpage() we
   zero out the page's content and don't submit any bio to read the page
   from the extent.

   Then it attempts to read the page at offset 20K entering
   btrfs_do_readpage() where we reuse the previously cached extent map
   (decided by get_extent_map()) since it spans the page's range and
   it's still in the inode's extent map tree.

   Just like for the previous page, we zero out the page's content since
   the extent map has the prealloc flag set.

   Then it attempts to read the page at offset 24K entering
   btrfs_do_readpage() where we reuse the previously cached extent map
   (decided by get_extent_map()) since it spans the page's range and
   it's still in the inode's extent map tree.

   Just like for the previous pages, we zero out the page's content since
   the extent map has the prealloc flag set. Note that we didn't lock the
   extent range [24K, 28K), so we didn't synchronize with the ongoing
   direct IO write being performed by task A;

5) Task A enters btrfs_create_dio_extent() and creates an ordered extent
   for the range [24K, 28K), with the flags BTRFS_ORDERED_DIRECT and
   BTRFS_ORDERED_PREALLOC set;

6) Task A unlocks the range [24K, 28K) at btrfs_dio_iomap_begin();

7) The ordered extent enters btrfs_finish_one_ordered() and locks the
   range [24K, 28K);

8) Task A enters fs/iomap/direct-io.c:iomap_dio_complete() and it tries
   to invalidate the page at offset 24K by calling
   kiocb_invalidate_post_direct_write(), resulting in a call chain that
   ends up at btrfs_release_folio().

   The btrfs_release_folio() call ends up returning false because the range
   for the page at file offset 24K is currently locked by the task doing
   the ordered extent completion in the previous step (7), so we have:

   btrfs_release_folio() ->
      __btrfs_release_folio() ->
         try_release_extent_mapping() ->
	     try_release_extent_state()

   This last function checking that the range is locked and returning false
   and propagating it up to btrfs_release_folio().

   So this results in a failure to invalidate the page and
   kiocb_invalidate_post_direct_write() triggers this message logged in
   dmesg:

     Page cache invalidation failure on direct I/O.  Possible data corruption due to collision with buffered I/O!

   After this we leave the page cache with stale data for the file range
   [24K, 28K), filled with zeroes instead of the data written by direct IO
   write (all bytes with a 0x01 value), so any task attempting to read with
   buffered IO, including the task that did the direct IO write, will get
   all bytes in the range with a 0x00 value instead of the written data.

Fix this by locking the range, with btrfs_lock_and_flush_ordered_range(),
at the two callers of btrfs_do_readpage() instead of doing it at
get_extent_map(), just like we did before commit ac325fc ("btrfs: do
not hold the extent lock for entire read"), and unlocking the range after
all the calls to btrfs_do_readpage(). This way we never reuse a cached
extent map without flushing any pending ordered extents from a concurrent
direct IO write.

Fixes: ac325fc ("btrfs: do not hold the extent lock for entire read")
Reviewed-by: Qu Wenruo <[email protected]>
Signed-off-by: Filipe Manana <[email protected]>
Signed-off-by: David Sterba <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
Gelbpunkt pushed a commit that referenced this pull request Mar 14, 2025
…O write

After commit ac325fc ("btrfs: do not hold the extent lock for entire
read") we can now trigger a race between a task doing a direct IO write
and readahead. When this race is triggered it results in tasks getting
stale data when they attempt do a buffered read (including the task that
did the direct IO write).

This race can be sporadically triggered with test case generic/418, failing
like this:

   $ ./check generic/418
   FSTYP         -- btrfs
   PLATFORM      -- Linux/x86_64 debian0 6.13.0-rc7-btrfs-next-185+ #17 SMP PREEMPT_DYNAMIC Mon Feb  3 12:28:46 WET 2025
   MKFS_OPTIONS  -- /dev/sdc
   MOUNT_OPTIONS -- /dev/sdc /home/fdmanana/btrfs-tests/scratch_1

   generic/418 14s ... - output mismatch (see /home/fdmanana/git/hub/xfstests/results//generic/418.out.bad)
       --- tests/generic/418.out	2020-06-10 19:29:03.850519863 +0100
       +++ /home/fdmanana/git/hub/xfstests/results//generic/418.out.bad	2025-02-03 15:42:36.974609476 +0000
       @@ -1,2 +1,5 @@
        QA output created by 418
       +cmpbuf: offset 0: Expected: 0x1, got 0x0
       +[6:0] FAIL - comparison failed, offset 24576
       +diotest -wp -b 4096 -n 8 -i 4 failed at loop 3
        Silence is golden
       ...
       (Run 'diff -u /home/fdmanana/git/hub/xfstests/tests/generic/418.out /home/fdmanana/git/hub/xfstests/results//generic/418.out.bad'  to see the entire diff)
   Ran: generic/418
   Failures: generic/418
   Failed 1 of 1 tests

The race happens like this:

1) A file has a prealloc extent for the range [16K, 28K);

2) Task A starts a direct IO write against file range [24K, 28K).
   At the start of the direct IO write it invalidates the page cache at
   __iomap_dio_rw() with kiocb_invalidate_pages() for the 4K page at file
   offset 24K;

3) Task A enters btrfs_dio_iomap_begin() and locks the extent range
   [24K, 28K);

4) Task B starts a readahead for file range [16K, 28K), entering
   btrfs_readahead().

   First it attempts to read the page at offset 16K by entering
   btrfs_do_readpage(), where it calls get_extent_map(), locks the range
   [16K, 20K) and gets the extent map for the range [16K, 28K), caching
   it into the 'em_cached' variable declared in the local stack of
   btrfs_readahead(), and then unlocks the range [16K, 20K).

   Since the extent map has the prealloc flag, at btrfs_do_readpage() we
   zero out the page's content and don't submit any bio to read the page
   from the extent.

   Then it attempts to read the page at offset 20K entering
   btrfs_do_readpage() where we reuse the previously cached extent map
   (decided by get_extent_map()) since it spans the page's range and
   it's still in the inode's extent map tree.

   Just like for the previous page, we zero out the page's content since
   the extent map has the prealloc flag set.

   Then it attempts to read the page at offset 24K entering
   btrfs_do_readpage() where we reuse the previously cached extent map
   (decided by get_extent_map()) since it spans the page's range and
   it's still in the inode's extent map tree.

   Just like for the previous pages, we zero out the page's content since
   the extent map has the prealloc flag set. Note that we didn't lock the
   extent range [24K, 28K), so we didn't synchronize with the ongoing
   direct IO write being performed by task A;

5) Task A enters btrfs_create_dio_extent() and creates an ordered extent
   for the range [24K, 28K), with the flags BTRFS_ORDERED_DIRECT and
   BTRFS_ORDERED_PREALLOC set;

6) Task A unlocks the range [24K, 28K) at btrfs_dio_iomap_begin();

7) The ordered extent enters btrfs_finish_one_ordered() and locks the
   range [24K, 28K);

8) Task A enters fs/iomap/direct-io.c:iomap_dio_complete() and it tries
   to invalidate the page at offset 24K by calling
   kiocb_invalidate_post_direct_write(), resulting in a call chain that
   ends up at btrfs_release_folio().

   The btrfs_release_folio() call ends up returning false because the range
   for the page at file offset 24K is currently locked by the task doing
   the ordered extent completion in the previous step (7), so we have:

   btrfs_release_folio() ->
      __btrfs_release_folio() ->
         try_release_extent_mapping() ->
	     try_release_extent_state()

   This last function checking that the range is locked and returning false
   and propagating it up to btrfs_release_folio().

   So this results in a failure to invalidate the page and
   kiocb_invalidate_post_direct_write() triggers this message logged in
   dmesg:

     Page cache invalidation failure on direct I/O.  Possible data corruption due to collision with buffered I/O!

   After this we leave the page cache with stale data for the file range
   [24K, 28K), filled with zeroes instead of the data written by direct IO
   write (all bytes with a 0x01 value), so any task attempting to read with
   buffered IO, including the task that did the direct IO write, will get
   all bytes in the range with a 0x00 value instead of the written data.

Fix this by locking the range, with btrfs_lock_and_flush_ordered_range(),
at the two callers of btrfs_do_readpage() instead of doing it at
get_extent_map(), just like we did before commit ac325fc ("btrfs: do
not hold the extent lock for entire read"), and unlocking the range after
all the calls to btrfs_do_readpage(). This way we never reuse a cached
extent map without flushing any pending ordered extents from a concurrent
direct IO write.

Fixes: ac325fc ("btrfs: do not hold the extent lock for entire read")
Reviewed-by: Qu Wenruo <[email protected]>
Signed-off-by: Filipe Manana <[email protected]>
Signed-off-by: David Sterba <[email protected]>
Gelbpunkt pushed a commit that referenced this pull request Mar 14, 2025
At btrfs_write_check() if our file's i_size is not sector size aligned and
we have a write that starts at an offset larger than the i_size that falls
within the same page of the i_size, then we end up not zeroing the file
range [i_size, write_offset).

The code is this:

    start_pos = round_down(pos, fs_info->sectorsize);
    oldsize = i_size_read(inode);
    if (start_pos > oldsize) {
        /* Expand hole size to cover write data, preventing empty gap */
        loff_t end_pos = round_up(pos + count, fs_info->sectorsize);

        ret = btrfs_cont_expand(BTRFS_I(inode), oldsize, end_pos);
        if (ret)
            return ret;
    }

So if our file's i_size is 90269 bytes and a write at offset 90365 bytes
comes in, we get 'start_pos' set to 90112 bytes, which is less than the
i_size and therefore we don't zero out the range [90269, 90365) by
calling btrfs_cont_expand().

This is an old bug introduced in commit 9036c10 ("Btrfs: update hole
handling v2"), from 2008, and the buggy code got moved around over the
years.

Fix this by discarding 'start_pos' and comparing against the write offset
('pos') without any alignment.

This bug was recently exposed by test case generic/363 which tests this
scenario by polluting ranges beyond EOF with an mmap write and than verify
that after a file increases we get zeroes for the range which is supposed
to be a hole and not what we wrote with the previous mmaped write.

We're only seeing this exposed now because generic/363 used to run only
on xfs until last Sunday's fstests update.

The test was failing like this:

   $ ./check generic/363
   FSTYP         -- btrfs
   PLATFORM      -- Linux/x86_64 debian0 6.13.0-rc7-btrfs-next-185+ #17 SMP PREEMPT_DYNAMIC Mon Feb  3 12:28:46 WET 2025
   MKFS_OPTIONS  -- /dev/sdc
   MOUNT_OPTIONS -- /dev/sdc /home/fdmanana/btrfs-tests/scratch_1

   generic/363 0s ... [failed, exit status 1]- output mismatch (see /home/fdmanana/git/hub/xfstests/results//generic/363.out.bad)
       --- tests/generic/363.out	2025-02-05 15:31:14.013646509 +0000
       +++ /home/fdmanana/git/hub/xfstests/results//generic/363.out.bad	2025-02-05 17:25:33.112630781 +0000
       @@ -1 +1,46 @@
        QA output created by 363
       +READ BAD DATA: offset = 0xdcad, size = 0xd921, fname = /home/fdmanana/btrfs-tests/dev/junk
       +OFFSET      GOOD    BAD     RANGE
       +0x1609d     0x0000  0x3104  0x0
       +operation# (mod 256) for the bad data may be 4
       +0x1609e     0x0000  0x0472  0x1
       +operation# (mod 256) for the bad data may be 4
       ...
       (Run 'diff -u /home/fdmanana/git/hub/xfstests/tests/generic/363.out /home/fdmanana/git/hub/xfstests/results//generic/363.out.bad'  to see the entire diff)
   Ran: generic/363
   Failures: generic/363
   Failed 1 of 1 tests

Fixes: 9036c10 ("Btrfs: update hole handling v2")
CC: [email protected]
Reviewed-by: Qu Wenruo <[email protected]>
Signed-off-by: Filipe Manana <[email protected]>
Signed-off-by: David Sterba <[email protected]>
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2 participants