linux.git/drivers/base/devcoredump.c, branch v7.2-rc1

devcoredump: Remove exit call

2026-05-22T11:26:51+00:00

Kconfig symbol DEV_COREDUMP is of type bool, therefore devcoredump
can't be built as a module and the exit code is a no-op.

Signed-off-by: Heiner Kallweit 
Link: https://patch.msgid.link/39a3821b-03d6-4ff0-97b7-82411a76d39a@gmail.com
Signed-off-by: Greg Kroah-Hartman

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook

devcoredump: Fix circular locking dependency with devcd->mutex.

2025-10-17T07:47:40+00:00

The original code causes a circular locking dependency found by lockdep.

======================================================
WARNING: possible circular locking dependency detected
6.16.0-rc6-lgci-xe-xe-pw-151626v3+ #1 Tainted: G S   U
------------------------------------------------------
xe_fault_inject/5091 is trying to acquire lock:
ffff888156815688 ((work_completion)(&(&devcd->del_wk)->work)){+.+.}-{0:0}, at: __flush_work+0x25d/0x660

but task is already holding lock:

ffff888156815620 (&devcd->mutex){+.+.}-{3:3}, at: dev_coredump_put+0x3f/0xa0
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&devcd->mutex){+.+.}-{3:3}:
       mutex_lock_nested+0x4e/0xc0
       devcd_data_write+0x27/0x90
       sysfs_kf_bin_write+0x80/0xf0
       kernfs_fop_write_iter+0x169/0x220
       vfs_write+0x293/0x560
       ksys_write+0x72/0xf0
       __x64_sys_write+0x19/0x30
       x64_sys_call+0x2bf/0x2660
       do_syscall_64+0x93/0xb60
       entry_SYSCALL_64_after_hwframe+0x76/0x7e
-> #1 (kn->active#236){++++}-{0:0}:
       kernfs_drain+0x1e2/0x200
       __kernfs_remove+0xae/0x400
       kernfs_remove_by_name_ns+0x5d/0xc0
       remove_files+0x54/0x70
       sysfs_remove_group+0x3d/0xa0
       sysfs_remove_groups+0x2e/0x60
       device_remove_attrs+0xc7/0x100
       device_del+0x15d/0x3b0
       devcd_del+0x19/0x30
       process_one_work+0x22b/0x6f0
       worker_thread+0x1e8/0x3d0
       kthread+0x11c/0x250
       ret_from_fork+0x26c/0x2e0
       ret_from_fork_asm+0x1a/0x30
-> #0 ((work_completion)(&(&devcd->del_wk)->work)){+.+.}-{0:0}:
       __lock_acquire+0x1661/0x2860
       lock_acquire+0xc4/0x2f0
       __flush_work+0x27a/0x660
       flush_delayed_work+0x5d/0xa0
       dev_coredump_put+0x63/0xa0
       xe_driver_devcoredump_fini+0x12/0x20 [xe]
       devm_action_release+0x12/0x30
       release_nodes+0x3a/0x120
       devres_release_all+0x8a/0xd0
       device_unbind_cleanup+0x12/0x80
       device_release_driver_internal+0x23a/0x280
       device_driver_detach+0x14/0x20
       unbind_store+0xaf/0xc0
       drv_attr_store+0x21/0x50
       sysfs_kf_write+0x4a/0x80
       kernfs_fop_write_iter+0x169/0x220
       vfs_write+0x293/0x560
       ksys_write+0x72/0xf0
       __x64_sys_write+0x19/0x30
       x64_sys_call+0x2bf/0x2660
       do_syscall_64+0x93/0xb60
       entry_SYSCALL_64_after_hwframe+0x76/0x7e
other info that might help us debug this:
Chain exists of: (work_completion)(&(&devcd->del_wk)->work) --> kn->active#236 --> &devcd->mutex
 Possible unsafe locking scenario:
       CPU0                    CPU1
       ----                    ----
  lock(&devcd->mutex);
                               lock(kn->active#236);
                               lock(&devcd->mutex);
  lock((work_completion)(&(&devcd->del_wk)->work));
 *** DEADLOCK ***
5 locks held by xe_fault_inject/5091:
 #0: ffff8881129f9488 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x72/0xf0
 #1: ffff88810c755078 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x123/0x220
 #2: ffff8881054811a0 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0x55/0x280
 #3: ffff888156815620 (&devcd->mutex){+.+.}-{3:3}, at: dev_coredump_put+0x3f/0xa0
 #4: ffffffff8359e020 (rcu_read_lock){....}-{1:2}, at: __flush_work+0x72/0x660
stack backtrace:
CPU: 14 UID: 0 PID: 5091 Comm: xe_fault_inject Tainted: G S   U              6.16.0-rc6-lgci-xe-xe-pw-151626v3+ #1 PREEMPT_{RT,(lazy)}
Tainted: [S]=CPU_OUT_OF_SPEC, [U]=USER
Hardware name: Micro-Star International Co., Ltd. MS-7D25/PRO Z690-A DDR4(MS-7D25), BIOS 1.10 12/13/2021
Call Trace:
 
 dump_stack_lvl+0x91/0xf0
 dump_stack+0x10/0x20
 print_circular_bug+0x285/0x360
 check_noncircular+0x135/0x150
 ? register_lock_class+0x48/0x4a0
 __lock_acquire+0x1661/0x2860
 lock_acquire+0xc4/0x2f0
 ? __flush_work+0x25d/0x660
 ? mark_held_locks+0x46/0x90
 ? __flush_work+0x25d/0x660
 __flush_work+0x27a/0x660
 ? __flush_work+0x25d/0x660
 ? trace_hardirqs_on+0x1e/0xd0
 ? __pfx_wq_barrier_func+0x10/0x10
 flush_delayed_work+0x5d/0xa0
 dev_coredump_put+0x63/0xa0
 xe_driver_devcoredump_fini+0x12/0x20 [xe]
 devm_action_release+0x12/0x30
 release_nodes+0x3a/0x120
 devres_release_all+0x8a/0xd0
 device_unbind_cleanup+0x12/0x80
 device_release_driver_internal+0x23a/0x280
 ? bus_find_device+0xa8/0xe0
 device_driver_detach+0x14/0x20
 unbind_store+0xaf/0xc0
 drv_attr_store+0x21/0x50
 sysfs_kf_write+0x4a/0x80
 kernfs_fop_write_iter+0x169/0x220
 vfs_write+0x293/0x560
 ksys_write+0x72/0xf0
 __x64_sys_write+0x19/0x30
 x64_sys_call+0x2bf/0x2660
 do_syscall_64+0x93/0xb60
 ? __f_unlock_pos+0x15/0x20
 ? __x64_sys_getdents64+0x9b/0x130
 ? __pfx_filldir64+0x10/0x10
 ? do_syscall_64+0x1a2/0xb60
 ? clear_bhb_loop+0x30/0x80
 ? clear_bhb_loop+0x30/0x80
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x76e292edd574
Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d d5 ea 0e 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 55 48 89 e5 48 83 ec 20 48 89
RSP: 002b:00007fffe247a828 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000076e292edd574
RDX: 000000000000000c RSI: 00006267f6306063 RDI: 000000000000000b
RBP: 000000000000000c R08: 000076e292fc4b20 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00006267f6306063
R13: 000000000000000b R14: 00006267e6859c00 R15: 000076e29322a000
 
xe 0000:03:00.0: [drm] Xe device coredump has been deleted.

Fixes: 01daccf74832 ("devcoredump : Serialize devcd_del work")
Cc: Mukesh Ojha 
Cc: Greg Kroah-Hartman 
Cc: Johannes Berg 
Cc: Rafael J. Wysocki 
Cc: Danilo Krummrich 
Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org # v6.1+
Signed-off-by: Maarten Lankhorst 
Cc: Matthew Brost 
Acked-by: Mukesh Ojha 
Link: https://lore.kernel.org/r/20250723142416.1020423-1-dev@lankhorst.se
Signed-off-by: Greg Kroah-Hartman

sysfs: treewide: switch back to attribute_group::bin_attrs

2025-06-17T08:44:15+00:00

The normal bin_attrs field can now handle const pointers.
This makes the _new variant unnecessary.
Switch all users back.

Signed-off-by: Thomas Weißschuh 
Link: https://lore.kernel.org/r/20250530-sysfs-const-bin_attr-final-v3-4-724bfcf05b99@weissschuh.net
Signed-off-by: Greg Kroah-Hartman

treewide: Switch/rename to timer_delete[_sync]()

2025-04-05T08:30:12+00:00

timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree
over and remove the historical wrapper inlines.

Conversion was done with coccinelle plus manual fixups where necessary.

Signed-off-by: Thomas Gleixner 
Signed-off-by: Ingo Molnar

devcoredump: Constify 'struct bin_attribute'

2025-01-15T17:30:58+00:00

The sysfs core now allows instances of 'struct bin_attribute' to be
moved into read-only memory. Make use of that to protect them against
accidental or malicious modifications.

Signed-off-by: Thomas Weißschuh 
Link: https://lore.kernel.org/r/20250114-sysfs-const-bin_attr-devcoredump-v1-2-fa93be30efae@weissschuh.net
Signed-off-by: Greg Kroah-Hartman

devcoredump: Define 'struct bin_attribute' through macro

2025-01-15T17:30:57+00:00

The macro saves some lines of code and simplifies the constification of
the attribute.

Signed-off-by: Thomas Weißschuh 
Link: https://lore.kernel.org/r/20250114-sysfs-const-bin_attr-devcoredump-v1-1-fa93be30efae@weissschuh.net
Signed-off-by: Greg Kroah-Hartman

devcoredump: cleanup some comments

2025-01-10T09:15:08+00:00

Correct a spello, remove an extra space between words, and fix
one kernel-doc warning:

drivers/base/devcoredump.c:292: warning: No description found for return value of 'devcd_read_from_sgtable'

Fixes: 522566376a3f ("devcoredump: add scatterlist support")
Fixes: 01daccf74832 ("devcoredump : Serialize devcd_del work")
Signed-off-by: Randy Dunlap 
Cc: Johannes Berg 
Cc: Greg Kroah-Hartman 
Cc: Rafael J. Wysocki 
Cc: Aviya Erenfeld 
Cc: Mukesh Ojha 
Link: https://lore.kernel.org/r/20241130023554.538820-1-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman

devcoredump: Add dev_coredumpm_timeout()

2024-06-12T15:29:36+00:00

Add function to set a custom coredump timeout.

For Xe driver usage, current 5 minutes timeout may be too short for
users to search and understand what needs to be done to capture
coredump to report bugs.

We have plans to automate(distribute a udev script) it but at the end
will be up to distros and users to pack it so having a option to
increase the timeout is a safer option.

v2:
- replace dev_coredump_timeout_set() by dev_coredumpm_timeout() (Mukesh)

v3:
- make dev_coredumpm() static inline (Johannes)

v5:
- rename DEVCOREDUMP_TIMEOUT -> DEVCD_TIMEOUT to avoid redefinition
in include/net/bluetooth/coredump.h

v6:
- fix definition of dev_coredumpm_timeout() when CONFIG_DEV_COREDUMP
is disabled

Cc: Rodrigo Vivi 
Cc: Mukesh Ojha 
Cc: Johannes Berg 
Cc: Jonathan Cavitt 
Reviewed-by: Rodrigo Vivi 
Reviewed-by: Jonathan Cavitt 
Signed-off-by: José Roberto de Souza 
Acked-by: Greg Kroah-Hartman 
Acked-by: Johannes Berg 
Link: https://patchwork.freedesktop.org/patch/msgid/20240611174716.72660-1-jose.souza@intel.com
Signed-off-by: Rodrigo Vivi

devcoredump: Add dev_coredump_put()

2024-04-11T13:39:48+00:00

It is useful for modules that do not want to keep coredump available
after its unload.
Otherwise, the coredump would only be removed after DEVCD_TIMEOUT
seconds.

v2:
- dev_coredump_put() documentation updated (Mukesh)

Cc: Rodrigo Vivi 
Cc: Mukesh Ojha 
Cc: Johannes Berg 
Cc: Jonathan Cavitt 
Reviewed-by: Johannes Berg 
Acked-by: Jonathan Cavitt 
Signed-off-by: José Roberto de Souza 
Acked-by: Greg Kroah-Hartman 
Link: https://patchwork.freedesktop.org/patch/msgid/20240409200206.108452-1-jose.souza@intel.com
Signed-off-by: Rodrigo Vivi