* [PATCH v5 0/3] Add support for long task name
@ 2025-07-16 12:39 Bhupesh
2025-07-16 12:39 ` [PATCH v5 1/3] exec: Remove obsolete comments Bhupesh
` (2 more replies)
0 siblings, 3 replies; 12+ messages in thread
From: Bhupesh @ 2025-07-16 12:39 UTC (permalink / raw)
To: akpm
Cc: bhupesh, kernel-dev, linux-kernel, bpf, linux-perf-users,
linux-fsdevel, linux-mm, oliver.sang, lkp, laoar.shao, pmladek,
rostedt, mathieu.desnoyers, arnaldo.melo, alexei.starovoitov,
andrii.nakryiko, mirq-linux, peterz, willy, david, viro, keescook,
ebiederm, brauner, jack, mingo, juri.lelli, bsegall, mgorman,
vschneid, linux-trace-kernel, kees, torvalds
Changes since v4:
================
- v4 can be seen here: https://lore.kernel.org/lkml/20250507110444.963779-1-bhupesh@igalia.com/
- As suggested by Kees, replaced tsk->comm with tsk->comm_str, inside 'task_struct'
where TASK_COMM_EXT_LEN is 64-bytes.
Changes since v3:
================
- v3 can be seen here: https://lore.kernel.org/lkml/20250507110444.963779-1-bhupesh@igalia.com/
- As suggested by Petr and Steven, used 'comm_ext' name instead of
'real_comm'. Correspondingly the macro name is changed to 'TASK_COMM_EXT_LEN'
for the 64-byte extended comm.
- Rebased this patchset on linux-next/master, which contain the following patch from
Steven now:
155fd6c3e2f0 ("tracing/sched: Use __string() instead of fixed lengths for task->comm")
- Accordingly, v4 drops the changes done for 'trace/sched' events in v3,
but retains the 'safe' memcpy' changes for other kernel trace users.
Changes since v2:
================
- v2 can be seen here: https://lore.kernel.org/lkml/20250331121820.455916-1-bhupesh@igalia.com/
- As suggested by Yafang and Kees, picked Linus' suggested approach for
this version (see: <https://lore.kernel.org/all/CAHk-=wjAmmHUg6vho1KjzQi2=psR30+CogFd4aXrThr2gsiS4g@mail.gmail.com/>).
- Dropped kthreads patch from this version. It would be sent out
separately, if we have a consensus on this approach.
Changes since v1:
================
- v1 can be seen here: https://lore.kernel.org/lkml/20250314052715.610377-1-bhupesh@igalia.com/
- As suggested by Kees, added [PATCH 3/3] to have a consistent
'full_name' entry inside 'task_struct' which both tasks and
kthreads can use.
- Fixed the commit message to indicate that the existing ABI
'/proc/$pid/task/$tid/comm' remains untouched and a parallel
'/proc/$pid/task/$tid/full_name' ABI for new (interested) users.
While working with user-space debugging tools which work especially
on linux gaming platforms, I found that the task name is truncated due
to the limitation of TASK_COMM_LEN.
Now, during debug tracing, seeing truncated names is not very useful,
especially on gaming platforms where the number of tasks running can
be very high.
This patchset does not touch 'TASK_COMM_LEN' at all, i.e.
'TASK_COMM_LEN' and the 16-byte design remains untouched.
Via this patchset, as Kees suggested 'tsk->comm' is replaced
with 'tsk->comm_str', inside 'task_struct':
union {
char comm_str[TASK_COMM_EXT_LEN];
};
where TASK_COMM_EXT_LEN is 64-bytes.
And then 'get_task_comm()' to pass 'tsk->comm_str'
to the existing users.
This would mean that ABI is maintained while ensuring that:
- Existing users of 'get_task_comm'/ 'set_task_comm' will get 'tsk->comm_str'
truncated to a maximum of 'TASK_COMM_LEN' (16-bytes) to maintain ABI,
- New / Modified users of 'get_task_comm'/ 'set_task_comm' will get
'tsk->comm_str' supported for a maximum of 'TASK_COMM_EXTLEN' (64-bytes).
Note, that the existing users have not been modified to migrate to
'TASK_COMM_EXT_LEN', in case they have hard-coded expectations of
dealing with only a 'TASK_COMM_LEN' long 'tsk->comm_str'.
After this change, gdb is able to show full name of the task, using a
simple app which generates threads with long names [see 1]:
# gdb ./threadnames -ex "run info thread" -ex "detach" -ex "quit" > log
# cat log
NameThatIsTooLongForComm[4662]
[1]. https://github.com/lostgoat/tasknames
Bhupesh (3):
exec: Remove obsolete comments
treewide: Switch memcpy() users of 'task->comm' to a more safer
implementation
treewide: Switch from tsk->comm to tsk->comm_str which is 64 bytes
long
arch/arm64/kernel/traps.c | 2 +-
arch/arm64/kvm/mmu.c | 2 +-
block/blk-core.c | 2 +-
block/bsg.c | 2 +-
drivers/char/random.c | 2 +-
drivers/hid/hid-core.c | 6 +++---
drivers/mmc/host/tmio_mmc_core.c | 6 +++---
drivers/pci/pci-sysfs.c | 2 +-
drivers/scsi/scsi_ioctl.c | 2 +-
drivers/tty/serial/serial_core.c | 2 +-
drivers/tty/tty_io.c | 8 ++++----
drivers/usb/core/devio.c | 16 ++++++++--------
drivers/usb/core/message.c | 2 +-
drivers/vfio/group.c | 2 +-
drivers/vfio/vfio_iommu_type1.c | 2 +-
drivers/vfio/vfio_main.c | 2 +-
drivers/xen/evtchn.c | 2 +-
drivers/xen/grant-table.c | 2 +-
fs/binfmt_elf.c | 2 +-
fs/coredump.c | 4 ++--
fs/drop_caches.c | 2 +-
fs/exec.c | 8 ++++----
fs/ext4/dir.c | 2 +-
fs/ext4/inode.c | 2 +-
fs/ext4/namei.c | 2 +-
fs/ext4/super.c | 12 ++++++------
fs/hugetlbfs/inode.c | 2 +-
fs/ioctl.c | 2 +-
fs/iomap/direct-io.c | 2 +-
fs/jbd2/transaction.c | 2 +-
fs/locks.c | 2 +-
fs/netfs/internal.h | 2 +-
fs/proc/base.c | 2 +-
fs/read_write.c | 2 +-
fs/splice.c | 2 +-
include/linux/coredump.h | 3 ++-
include/linux/filter.h | 2 +-
include/linux/ratelimit.h | 2 +-
include/linux/sched.h | 17 ++++++++++-------
include/trace/events/block.h | 5 +++++
include/trace/events/oom.h | 1 +
include/trace/events/osnoise.h | 1 +
include/trace/events/signal.h | 1 +
include/trace/events/task.h | 2 ++
init/init_task.c | 2 +-
ipc/sem.c | 2 +-
kernel/acct.c | 2 +-
kernel/audit.c | 4 ++--
kernel/auditsc.c | 10 +++++-----
kernel/bpf/helpers.c | 2 +-
kernel/capability.c | 4 ++--
kernel/cgroup/cgroup-v1.c | 2 +-
kernel/cred.c | 4 ++--
kernel/events/core.c | 2 +-
kernel/exit.c | 6 +++---
kernel/fork.c | 9 +++++++--
kernel/freezer.c | 4 ++--
kernel/futex/waitwake.c | 2 +-
kernel/hung_task.c | 10 +++++-----
kernel/irq/manage.c | 2 +-
kernel/kthread.c | 2 +-
kernel/locking/rtmutex.c | 2 +-
kernel/printk/printk.c | 2 +-
kernel/sched/core.c | 22 +++++++++++-----------
kernel/sched/debug.c | 4 ++--
kernel/signal.c | 6 +++---
kernel/sys.c | 6 +++---
kernel/sysctl.c | 2 +-
kernel/time/itimer.c | 4 ++--
kernel/time/posix-cpu-timers.c | 2 +-
kernel/tsacct.c | 2 +-
kernel/workqueue.c | 6 +++---
lib/dump_stack.c | 2 +-
lib/nlattr.c | 6 +++---
mm/compaction.c | 2 +-
mm/filemap.c | 4 ++--
mm/gup.c | 2 +-
mm/memfd.c | 2 +-
mm/memory-failure.c | 10 +++++-----
mm/memory.c | 2 +-
mm/mmap.c | 4 ++--
mm/oom_kill.c | 18 +++++++++---------
mm/page_alloc.c | 4 ++--
mm/util.c | 2 +-
net/core/sock.c | 2 +-
net/dns_resolver/internal.h | 2 +-
net/ipv4/raw.c | 2 +-
net/ipv4/tcp.c | 2 +-
net/socket.c | 2 +-
security/lsm_audit.c | 4 ++--
90 files changed, 184 insertions(+), 165 deletions(-)
--
2.38.1
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH v5 1/3] exec: Remove obsolete comments
2025-07-16 12:39 [PATCH v5 0/3] Add support for long task name Bhupesh
@ 2025-07-16 12:39 ` Bhupesh
2025-07-16 12:39 ` [PATCH v5 2/3] treewide: Switch memcpy() users of 'task->comm' to a more safer implementation Bhupesh
2025-07-16 12:39 ` [PATCH v5 3/3] treewide: Switch from tsk->comm to tsk->comm_str which is 64 bytes long Bhupesh
2 siblings, 0 replies; 12+ messages in thread
From: Bhupesh @ 2025-07-16 12:39 UTC (permalink / raw)
To: akpm
Cc: bhupesh, kernel-dev, linux-kernel, bpf, linux-perf-users,
linux-fsdevel, linux-mm, oliver.sang, lkp, laoar.shao, pmladek,
rostedt, mathieu.desnoyers, arnaldo.melo, alexei.starovoitov,
andrii.nakryiko, mirq-linux, peterz, willy, david, viro, keescook,
ebiederm, brauner, jack, mingo, juri.lelli, bsegall, mgorman,
vschneid, linux-trace-kernel, kees, torvalds
Patch 3a3f61ce5e0b ("exec: Make sure task->comm is always NUL-terminated"),
replaced 'strscpy_pad()' with 'memcpy()' implementations inside
'__set_task_comm()'.
However a few left-over comments are still there, which mention
the usage of 'strscpy_pad()' inside '__set_task_comm()'.
Remove those obsolete comments.
While at it, also remove an obsolete comment regarding 'task_lock()'
usage while handing 'task->comm'.
Signed-off-by: Bhupesh <bhupesh@igalia.com>
---
include/linux/sched.h | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/include/linux/sched.h b/include/linux/sched.h
index d64d3e89bd11..a4a23267a982 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1155,10 +1155,8 @@ struct task_struct {
*
* - normally initialized begin_new_exec()
* - set it with set_task_comm()
- * - strscpy_pad() to ensure it is always NUL-terminated and
+ * - logic inside set_task_comm() will ensure it is always NUL-terminated and
* zero-padded
- * - task_lock() to ensure the operation is atomic and the name is
- * fully updated.
*/
char comm[TASK_COMM_LEN];
@@ -1952,7 +1950,7 @@ extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec
* User space can randomly change their names anyway, so locking for readers
* doesn't make sense. For writers, locking is probably necessary, as a race
* condition could lead to long-term mixed results.
- * The strscpy_pad() in __set_task_comm() can ensure that the task comm is
+ * The logic inside __set_task_comm() should ensure that the task comm is
* always NUL-terminated and zero-padded. Therefore the race condition between
* reader and writer is not an issue.
*
--
2.38.1
^ permalink raw reply related [flat|nested] 12+ messages in thread
* [PATCH v5 2/3] treewide: Switch memcpy() users of 'task->comm' to a more safer implementation
2025-07-16 12:39 [PATCH v5 0/3] Add support for long task name Bhupesh
2025-07-16 12:39 ` [PATCH v5 1/3] exec: Remove obsolete comments Bhupesh
@ 2025-07-16 12:39 ` Bhupesh
2025-07-16 12:39 ` [PATCH v5 3/3] treewide: Switch from tsk->comm to tsk->comm_str which is 64 bytes long Bhupesh
2 siblings, 0 replies; 12+ messages in thread
From: Bhupesh @ 2025-07-16 12:39 UTC (permalink / raw)
To: akpm
Cc: bhupesh, kernel-dev, linux-kernel, bpf, linux-perf-users,
linux-fsdevel, linux-mm, oliver.sang, lkp, laoar.shao, pmladek,
rostedt, mathieu.desnoyers, arnaldo.melo, alexei.starovoitov,
andrii.nakryiko, mirq-linux, peterz, willy, david, viro, keescook,
ebiederm, brauner, jack, mingo, juri.lelli, bsegall, mgorman,
vschneid, linux-trace-kernel, kees, torvalds
As Linus mentioned in [1], currently we have several memcpy() use-cases
which use 'current->comm' to copy the task name over to local copies.
For an example:
...
char comm[TASK_COMM_LEN];
memcpy(comm, current->comm, TASK_COMM_LEN);
...
These should be modified so that we can later implement approaches
to handle the task->comm's 16-byte length limitation (TASK_COMM_LEN)
in a more modular way (follow-up patch does the same):
...
char comm[TASK_COMM_LEN];
memcpy(comm, current->comm, TASK_COMM_LEN);
comm[TASK_COMM_LEN - 1] = '\0';
...
The relevant 'memcpy()' users were identified using the following search
pattern:
$ git grep 'memcpy.*->comm\>'
[1]. https://lore.kernel.org/all/CAHk-=wjAmmHUg6vho1KjzQi2=psR30+CogFd4aXrThr2gsiS4g@mail.gmail.com/
Signed-off-by: Bhupesh <bhupesh@igalia.com>
---
include/linux/coredump.h | 3 ++-
include/trace/events/block.h | 5 +++++
include/trace/events/oom.h | 1 +
include/trace/events/osnoise.h | 1 +
include/trace/events/signal.h | 1 +
include/trace/events/task.h | 2 ++
6 files changed, 12 insertions(+), 1 deletion(-)
diff --git a/include/linux/coredump.h b/include/linux/coredump.h
index 68861da4cf7c..988b233dcc09 100644
--- a/include/linux/coredump.h
+++ b/include/linux/coredump.h
@@ -54,7 +54,8 @@ extern void vfs_coredump(const kernel_siginfo_t *siginfo);
do { \
char comm[TASK_COMM_LEN]; \
/* This will always be NUL terminated. */ \
- memcpy(comm, current->comm, sizeof(comm)); \
+ memcpy(comm, current->comm, TASK_COMM_LEN); \
+ comm[TASK_COMM_LEN - 1] = '\0'; \
printk_ratelimited(Level "coredump: %d(%*pE): " Format "\n", \
task_tgid_vnr(current), (int)strlen(comm), comm, ##__VA_ARGS__); \
} while (0) \
diff --git a/include/trace/events/block.h b/include/trace/events/block.h
index 3e582d5e3a57..af40096a7114 100644
--- a/include/trace/events/block.h
+++ b/include/trace/events/block.h
@@ -214,6 +214,7 @@ DECLARE_EVENT_CLASS(block_rq,
blk_fill_rwbs(__entry->rwbs, rq->cmd_flags);
__get_str(cmd)[0] = '\0';
memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
+ __entry->comm[TASK_COMM_LEN - 1] = '\0';
),
TP_printk("%d,%d %s %u (%s) %llu + %u %s,%u,%u [%s]",
@@ -352,6 +353,7 @@ DECLARE_EVENT_CLASS(block_bio,
__entry->nr_sector = bio_sectors(bio);
blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
+ __entry->comm[TASK_COMM_LEN - 1] = '\0';
),
TP_printk("%d,%d %s %llu + %u [%s]",
@@ -435,6 +437,7 @@ TRACE_EVENT(block_plug,
TP_fast_assign(
memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
+ __entry->comm[TASK_COMM_LEN - 1] = '\0';
),
TP_printk("[%s]", __entry->comm)
@@ -454,6 +457,7 @@ DECLARE_EVENT_CLASS(block_unplug,
TP_fast_assign(
__entry->nr_rq = depth;
memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
+ __entry->comm[TASK_COMM_LEN - 1] = '\0';
),
TP_printk("[%s] %d", __entry->comm, __entry->nr_rq)
@@ -505,6 +509,7 @@ TRACE_EVENT(block_split,
__entry->new_sector = new_sector;
blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
+ __entry->comm[TASK_COMM_LEN - 1] = '\0';
),
TP_printk("%d,%d %s %llu / %llu [%s]",
diff --git a/include/trace/events/oom.h b/include/trace/events/oom.h
index 9f0a5d1482c4..a5641ed4285f 100644
--- a/include/trace/events/oom.h
+++ b/include/trace/events/oom.h
@@ -24,6 +24,7 @@ TRACE_EVENT(oom_score_adj_update,
TP_fast_assign(
__entry->pid = task->pid;
memcpy(__entry->comm, task->comm, TASK_COMM_LEN);
+ __entry->comm[TASK_COMM_LEN - 1] = '\0';
__entry->oom_score_adj = task->signal->oom_score_adj;
),
diff --git a/include/trace/events/osnoise.h b/include/trace/events/osnoise.h
index 3f4273623801..0321b3f8d532 100644
--- a/include/trace/events/osnoise.h
+++ b/include/trace/events/osnoise.h
@@ -117,6 +117,7 @@ TRACE_EVENT(thread_noise,
TP_fast_assign(
memcpy(__entry->comm, t->comm, TASK_COMM_LEN);
+ __entry->comm[TASK_COMM_LEN - 1] = '\0';
__entry->pid = t->pid;
__entry->start = start;
__entry->duration = duration;
diff --git a/include/trace/events/signal.h b/include/trace/events/signal.h
index 1db7e4b07c01..7f490e553db5 100644
--- a/include/trace/events/signal.h
+++ b/include/trace/events/signal.h
@@ -68,6 +68,7 @@ TRACE_EVENT(signal_generate,
__entry->sig = sig;
TP_STORE_SIGINFO(__entry, info);
memcpy(__entry->comm, task->comm, TASK_COMM_LEN);
+ __entry->comm[TASK_COMM_LEN - 1] = '\0';
__entry->pid = task->pid;
__entry->group = group;
__entry->result = result;
diff --git a/include/trace/events/task.h b/include/trace/events/task.h
index af535b053033..4ddf21b69372 100644
--- a/include/trace/events/task.h
+++ b/include/trace/events/task.h
@@ -22,6 +22,7 @@ TRACE_EVENT(task_newtask,
TP_fast_assign(
__entry->pid = task->pid;
memcpy(__entry->comm, task->comm, TASK_COMM_LEN);
+ __entry->comm[TASK_COMM_LEN - 1] = '\0';
__entry->clone_flags = clone_flags;
__entry->oom_score_adj = task->signal->oom_score_adj;
),
@@ -45,6 +46,7 @@ TRACE_EVENT(task_rename,
TP_fast_assign(
memcpy(entry->oldcomm, task->comm, TASK_COMM_LEN);
+ entry->oldcomm[TASK_COMM_LEN - 1] = '\0';
strscpy(entry->newcomm, comm, TASK_COMM_LEN);
__entry->oom_score_adj = task->signal->oom_score_adj;
),
--
2.38.1
^ permalink raw reply related [flat|nested] 12+ messages in thread
* [PATCH v5 3/3] treewide: Switch from tsk->comm to tsk->comm_str which is 64 bytes long
2025-07-16 12:39 [PATCH v5 0/3] Add support for long task name Bhupesh
2025-07-16 12:39 ` [PATCH v5 1/3] exec: Remove obsolete comments Bhupesh
2025-07-16 12:39 ` [PATCH v5 2/3] treewide: Switch memcpy() users of 'task->comm' to a more safer implementation Bhupesh
@ 2025-07-16 12:39 ` Bhupesh
2025-07-16 18:10 ` Andrii Nakryiko
` (2 more replies)
2 siblings, 3 replies; 12+ messages in thread
From: Bhupesh @ 2025-07-16 12:39 UTC (permalink / raw)
To: akpm
Cc: bhupesh, kernel-dev, linux-kernel, bpf, linux-perf-users,
linux-fsdevel, linux-mm, oliver.sang, lkp, laoar.shao, pmladek,
rostedt, mathieu.desnoyers, arnaldo.melo, alexei.starovoitov,
andrii.nakryiko, mirq-linux, peterz, willy, david, viro, keescook,
ebiederm, brauner, jack, mingo, juri.lelli, bsegall, mgorman,
vschneid, linux-trace-kernel, kees, torvalds
Historically due to the 16-byte length of TASK_COMM_LEN, the
users of 'tsk->comm' are restricted to use a fixed-size target
buffer also of TASK_COMM_LEN for 'memcpy()' like use-cases.
To fix the same, Kees suggested in [1] that we can replace tsk->comm,
with tsk->comm_str, inside 'task_struct':
union {
char comm_str[TASK_COMM_EXT_LEN];
};
where TASK_COMM_EXT_LEN is 64-bytes.
And then modify 'get_task_comm()' to pass 'tsk->comm_str'
to the existing users.
This would mean that ABI is maintained while ensuring that:
- Existing users of 'get_task_comm'/ 'set_task_comm' will get 'tsk->comm_str'
truncated to a maximum of 'TASK_COMM_LEN' (16-bytes) to maintain ABI,
- New / Modified users of 'get_task_comm'/ 'set_task_comm' will get
'tsk->comm_str' supported for a maximum of 'TASK_COMM_EXTLEN' (64-bytes).
Note, that the existing users have not been modified to migrate to
'TASK_COMM_EXT_LEN', in case they have hard-coded expectations of
dealing with only a 'TASK_COMM_LEN' long 'tsk->comm_str'.
[1]. https://lore.kernel.org/all/202505231346.52F291C54@keescook/
Signed-off-by: Bhupesh <bhupesh@igalia.com>
---
arch/arm64/kernel/traps.c | 2 +-
arch/arm64/kvm/mmu.c | 2 +-
block/blk-core.c | 2 +-
block/bsg.c | 2 +-
drivers/char/random.c | 2 +-
drivers/hid/hid-core.c | 6 +++---
drivers/mmc/host/tmio_mmc_core.c | 6 +++---
drivers/pci/pci-sysfs.c | 2 +-
drivers/scsi/scsi_ioctl.c | 2 +-
drivers/tty/serial/serial_core.c | 2 +-
drivers/tty/tty_io.c | 8 ++++----
drivers/usb/core/devio.c | 16 ++++++++--------
drivers/usb/core/message.c | 2 +-
drivers/vfio/group.c | 2 +-
drivers/vfio/vfio_iommu_type1.c | 2 +-
drivers/vfio/vfio_main.c | 2 +-
drivers/xen/evtchn.c | 2 +-
drivers/xen/grant-table.c | 2 +-
fs/binfmt_elf.c | 2 +-
fs/coredump.c | 4 ++--
fs/drop_caches.c | 2 +-
fs/exec.c | 8 ++++----
fs/ext4/dir.c | 2 +-
fs/ext4/inode.c | 2 +-
fs/ext4/namei.c | 2 +-
fs/ext4/super.c | 12 ++++++------
fs/hugetlbfs/inode.c | 2 +-
fs/ioctl.c | 2 +-
fs/iomap/direct-io.c | 2 +-
fs/jbd2/transaction.c | 2 +-
fs/locks.c | 2 +-
fs/netfs/internal.h | 2 +-
fs/proc/base.c | 2 +-
fs/read_write.c | 2 +-
fs/splice.c | 2 +-
include/linux/coredump.h | 2 +-
include/linux/filter.h | 2 +-
include/linux/ratelimit.h | 2 +-
include/linux/sched.h | 11 ++++++++---
init/init_task.c | 2 +-
ipc/sem.c | 2 +-
kernel/acct.c | 2 +-
kernel/audit.c | 4 ++--
kernel/auditsc.c | 10 +++++-----
kernel/bpf/helpers.c | 2 +-
kernel/capability.c | 4 ++--
kernel/cgroup/cgroup-v1.c | 2 +-
kernel/cred.c | 4 ++--
kernel/events/core.c | 2 +-
kernel/exit.c | 6 +++---
kernel/fork.c | 9 +++++++--
kernel/freezer.c | 4 ++--
kernel/futex/waitwake.c | 2 +-
kernel/hung_task.c | 10 +++++-----
kernel/irq/manage.c | 2 +-
kernel/kthread.c | 2 +-
kernel/locking/rtmutex.c | 2 +-
kernel/printk/printk.c | 2 +-
kernel/sched/core.c | 22 +++++++++++-----------
kernel/sched/debug.c | 4 ++--
kernel/signal.c | 6 +++---
kernel/sys.c | 6 +++---
kernel/sysctl.c | 2 +-
kernel/time/itimer.c | 4 ++--
kernel/time/posix-cpu-timers.c | 2 +-
kernel/tsacct.c | 2 +-
kernel/workqueue.c | 6 +++---
lib/dump_stack.c | 2 +-
lib/nlattr.c | 6 +++---
mm/compaction.c | 2 +-
mm/filemap.c | 4 ++--
mm/gup.c | 2 +-
mm/memfd.c | 2 +-
mm/memory-failure.c | 10 +++++-----
mm/memory.c | 2 +-
mm/mmap.c | 4 ++--
mm/oom_kill.c | 18 +++++++++---------
mm/page_alloc.c | 4 ++--
mm/util.c | 2 +-
net/core/sock.c | 2 +-
net/dns_resolver/internal.h | 2 +-
net/ipv4/raw.c | 2 +-
net/ipv4/tcp.c | 2 +-
net/socket.c | 2 +-
security/lsm_audit.c | 4 ++--
85 files changed, 171 insertions(+), 161 deletions(-)
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index bed754b736d3..689c2b145fa1 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -245,7 +245,7 @@ static void arm64_show_signal(int signo, const char *str)
!__ratelimit(&rs))
return;
- pr_info("%s[%d]: unhandled exception: ", tsk->comm, task_pid_nr(tsk));
+ pr_info("%s[%d]: unhandled exception: ", tsk->comm_str, task_pid_nr(tsk));
if (esr)
pr_cont("%s, ESR 0x%016lx, ", esr_get_class_string(esr), esr);
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 1c78864767c5..c86ab5ae4532 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -891,7 +891,7 @@ static int kvm_init_ipa_range(struct kvm_s2_mmu *mmu, unsigned long type)
phys_shift = KVM_PHYS_SHIFT;
if (phys_shift > kvm_ipa_limit) {
pr_warn_once("%s using unsupported default IPA limit, upgrade your VMM\n",
- current->comm);
+ current->comm_str);
return -EINVAL;
}
}
diff --git a/block/blk-core.c b/block/blk-core.c
index fdac48aec5ef..f93e2a1676b6 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -562,7 +562,7 @@ static inline int bio_check_eod(struct bio *bio)
bio->bi_iter.bi_sector > maxsector - nr_sectors)) {
pr_info_ratelimited("%s: attempt to access beyond end of device\n"
"%pg: rw=%d, sector=%llu, nr_sectors = %u limit=%llu\n",
- current->comm, bio->bi_bdev, bio->bi_opf,
+ current->comm_str, bio->bi_bdev, bio->bi_opf,
bio->bi_iter.bi_sector, nr_sectors, maxsector);
return -EIO;
}
diff --git a/block/bsg.c b/block/bsg.c
index 72157a59b788..1f348e798cfa 100644
--- a/block/bsg.c
+++ b/block/bsg.c
@@ -151,7 +151,7 @@ static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
return bsg_sg_io(bd, file->f_mode & FMODE_WRITE, uarg);
case SCSI_IOCTL_SEND_COMMAND:
pr_warn_ratelimited("%s: calling unsupported SCSI_IOCTL_SEND_COMMAND\n",
- current->comm);
+ current->comm_str);
return -EINVAL;
default:
return -ENOTTY;
diff --git a/drivers/char/random.c b/drivers/char/random.c
index d45383d57919..6f28a4d9af4a 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -1477,7 +1477,7 @@ static ssize_t urandom_read_iter(struct kiocb *kiocb, struct iov_iter *iter)
else if (ratelimit_disable || __ratelimit(&urandom_warning)) {
--maxwarn;
pr_notice("%s: uninitialized urandom read (%zu bytes read)\n",
- current->comm, iov_iter_count(iter));
+ current->comm_str, iov_iter_count(iter));
}
}
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 2930d6e23d40..f5b75c5837ff 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1405,7 +1405,7 @@ u32 hid_field_extract(const struct hid_device *hid, u8 *report,
{
if (n > 32) {
hid_warn_once(hid, "%s() called with n (%d) > 32! (%s)\n",
- __func__, n, current->comm);
+ __func__, n, current->comm_str);
n = 32;
}
@@ -1451,7 +1451,7 @@ static void implement(const struct hid_device *hid, u8 *report,
{
if (unlikely(n > 32)) {
hid_warn(hid, "%s() called with n (%d) > 32! (%s)\n",
- __func__, n, current->comm);
+ __func__, n, current->comm_str);
n = 32;
} else if (n < 32) {
u32 m = (1U << n) - 1;
@@ -1459,7 +1459,7 @@ static void implement(const struct hid_device *hid, u8 *report,
if (unlikely(value > m)) {
hid_warn(hid,
"%s() called with too large value %d (n: %d)! (%s)\n",
- __func__, value, n, current->comm);
+ __func__, value, n, current->comm_str);
value &= m;
}
}
diff --git a/drivers/mmc/host/tmio_mmc_core.c b/drivers/mmc/host/tmio_mmc_core.c
index 21c2f9095bac..aa083b919532 100644
--- a/drivers/mmc/host/tmio_mmc_core.c
+++ b/drivers/mmc/host/tmio_mmc_core.c
@@ -951,13 +951,13 @@ static void tmio_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
if (IS_ERR(host->mrq)) {
dev_dbg(dev,
"%s.%d: concurrent .set_ios(), clk %u, mode %u\n",
- current->comm, task_pid_nr(current),
+ current->comm_str, task_pid_nr(current),
ios->clock, ios->power_mode);
host->mrq = ERR_PTR(-EINTR);
} else {
dev_dbg(dev,
"%s.%d: CMD%u active since %lu, now %lu!\n",
- current->comm, task_pid_nr(current),
+ current->comm_str, task_pid_nr(current),
host->mrq->cmd->opcode, host->last_req_ts,
jiffies);
}
@@ -1000,7 +1000,7 @@ static void tmio_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
if (PTR_ERR(host->mrq) == -EINTR)
dev_dbg(&host->pdev->dev,
"%s.%d: IOS interrupted: clk %u, mode %u",
- current->comm, task_pid_nr(current),
+ current->comm_str, task_pid_nr(current),
ios->clock, ios->power_mode);
/* Ready for new mrqs */
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 5eea14c1f7f5..a59458f1b091 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -786,7 +786,7 @@ static ssize_t pci_write_config(struct file *filp, struct kobject *kobj,
if (resource_is_exclusive(&dev->driver_exclusive_resource, off,
count)) {
pci_warn_once(dev, "%s: Unexpected write to kernel-exclusive config offset %llx",
- current->comm, off);
+ current->comm_str, off);
add_taint(TAINT_USER, LOCKDEP_STILL_OK);
}
diff --git a/drivers/scsi/scsi_ioctl.c b/drivers/scsi/scsi_ioctl.c
index 0ddc95bafc71..4afeee7e9dec 100644
--- a/drivers/scsi/scsi_ioctl.c
+++ b/drivers/scsi/scsi_ioctl.c
@@ -894,7 +894,7 @@ int scsi_ioctl(struct scsi_device *sdev, bool open_for_write, int cmd,
case SCSI_IOCTL_START_UNIT:
case SCSI_IOCTL_STOP_UNIT:
printk(KERN_WARNING "program %s is using a deprecated SCSI "
- "ioctl, please convert it to SG_IO\n", current->comm);
+ "ioctl, please convert it to SG_IO\n", current->comm_str);
break;
default:
break;
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 86d404d649a3..66beaa8de571 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -1017,7 +1017,7 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port,
if (uport->flags & UPF_SPD_MASK) {
dev_notice_ratelimited(uport->dev,
"%s sets custom speed on %s. This is deprecated.\n",
- current->comm,
+ current->comm_str,
tty_name(port->tty));
}
uart_change_line_settings(tty, state, NULL);
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index e2d92cf70eb7..d354b0d986e7 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -2618,7 +2618,7 @@ static int tty_set_serial(struct tty_struct *tty, struct serial_struct *ss)
if (flags)
pr_warn_ratelimited("%s: '%s' is using deprecated serial flags (with no effect): %.8x\n",
- __func__, current->comm, flags);
+ __func__, current->comm_str, flags);
if (!tty->ops->set_serial)
return -ENOTTY;
@@ -3030,7 +3030,7 @@ void __do_SAK(struct tty_struct *tty)
/* Kill the entire session */
do_each_pid_task(session, PIDTYPE_SID, p) {
tty_notice(tty, "SAK: killed process %d (%s): by session\n",
- task_pid_nr(p), p->comm);
+ task_pid_nr(p), p->comm_str);
group_send_sig_info(SIGKILL, SEND_SIG_PRIV, p, PIDTYPE_SID);
} while_each_pid_task(session, PIDTYPE_SID, p);
@@ -3038,7 +3038,7 @@ void __do_SAK(struct tty_struct *tty)
for_each_process_thread(g, p) {
if (p->signal->tty == tty) {
tty_notice(tty, "SAK: killed process %d (%s): by controlling tty\n",
- task_pid_nr(p), p->comm);
+ task_pid_nr(p), p->comm_str);
group_send_sig_info(SIGKILL, SEND_SIG_PRIV, p,
PIDTYPE_SID);
continue;
@@ -3047,7 +3047,7 @@ void __do_SAK(struct tty_struct *tty)
i = iterate_fd(p->files, 0, this_tty, tty);
if (i != 0) {
tty_notice(tty, "SAK: killed process %d (%s): by fd#%d\n",
- task_pid_nr(p), p->comm, i - 1);
+ task_pid_nr(p), p->comm_str, i - 1);
group_send_sig_info(SIGKILL, SEND_SIG_PRIV, p,
PIDTYPE_SID);
}
diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c
index f6ce6e26e0d4..663e752aaa7c 100644
--- a/drivers/usb/core/devio.c
+++ b/drivers/usb/core/devio.c
@@ -849,7 +849,7 @@ static int checkintf(struct usb_dev_state *ps, unsigned int ifnum)
/* if not yet claimed, claim it for the driver */
dev_warn(&ps->dev->dev, "usbfs: process %d (%s) did not claim "
"interface %u before use\n", task_pid_nr(current),
- current->comm, ifnum);
+ current->comm_str, ifnum);
return claimintf(ps, ifnum);
}
@@ -924,7 +924,7 @@ static int check_ctrlrecip(struct usb_dev_state *ps, unsigned int requesttype,
dev_info(&ps->dev->dev,
"%s: process %i (%s) requesting ep %02x but needs %02x\n",
__func__, task_pid_nr(current),
- current->comm, index, index ^ 0x80);
+ current->comm_str, index, index ^ 0x80);
}
if (ret >= 0)
ret = checkintf(ps, ret);
@@ -1078,7 +1078,7 @@ static int usbdev_open(struct inode *inode, struct file *file)
file->private_data = ps;
usb_unlock_device(dev);
snoop(&dev->dev, "opened by process %d: %s\n", task_pid_nr(current),
- current->comm);
+ current->comm_str);
return ret;
out_unlock_device:
@@ -1257,7 +1257,7 @@ static int do_proc_control(struct usb_dev_state *ps,
if (i < 0 && i != -EPIPE) {
dev_printk(KERN_DEBUG, &dev->dev, "usbfs: USBDEVFS_CONTROL "
"failed cmd %s rqt %u rq %u len %u ret %d\n",
- current->comm, ctrl->bRequestType, ctrl->bRequest,
+ current->comm_str, ctrl->bRequestType, ctrl->bRequest,
ctrl->wLength, i);
}
ret = (i < 0 ? i : actlen);
@@ -1389,7 +1389,7 @@ static void check_reset_of_active_ep(struct usb_device *udev,
ep = eps[epnum & 0x0f];
if (ep && !list_empty(&ep->urb_list))
dev_warn(&udev->dev, "Process %d (%s) called USBDEVFS_%s for active endpoint 0x%02x\n",
- task_pid_nr(current), current->comm,
+ task_pid_nr(current), current->comm_str,
ioctl_name, epnum);
}
@@ -1517,7 +1517,7 @@ static int proc_resetdevice(struct usb_dev_state *ps)
!test_bit(number, &ps->ifclaimed)) {
dev_warn(&ps->dev->dev,
"usbfs: interface %d claimed by %s while '%s' resets device\n",
- number, interface->dev.driver->name, current->comm);
+ number, interface->dev.driver->name, current->comm_str);
return -EACCES;
}
}
@@ -1571,7 +1571,7 @@ static int proc_setconfig(struct usb_dev_state *ps, void __user *arg)
->desc.bInterfaceNumber,
actconfig->interface[i]
->dev.driver->name,
- current->comm, u);
+ current->comm_str, u);
status = -EBUSY;
break;
}
@@ -2428,7 +2428,7 @@ static int proc_claim_port(struct usb_dev_state *ps, void __user *arg)
rc = usb_hub_claim_port(ps->dev, portnum, ps);
if (rc == 0)
snoop(&ps->dev->dev, "port %d claimed by process %d: %s\n",
- portnum, task_pid_nr(current), current->comm);
+ portnum, task_pid_nr(current), current->comm_str);
return rc;
}
diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
index d2b2787be409..d33e8881281c 100644
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -67,7 +67,7 @@ static int usb_start_wait_urb(struct urb *urb, int timeout, int *actual_length)
dev_dbg(&urb->dev->dev,
"%s timed out on ep%d%s len=%u/%u\n",
- current->comm,
+ current->comm_str,
usb_endpoint_num(&urb->ep->desc),
usb_urb_dir_in(urb) ? "in" : "out",
urb->actual_length,
diff --git a/drivers/vfio/group.c b/drivers/vfio/group.c
index c376a6279de0..991ca92e9eee 100644
--- a/drivers/vfio/group.c
+++ b/drivers/vfio/group.c
@@ -280,7 +280,7 @@ static struct file *vfio_device_open_file(struct vfio_device *device)
if (device->group->type == VFIO_NO_IOMMU)
dev_warn(device->dev, "vfio-noiommu device opened by user "
- "(%s:%d)\n", current->comm, task_pid_nr(current));
+ "(%s:%d)\n", current->comm_str, task_pid_nr(current));
/*
* On success the ref of device is moved to the file and
* put in vfio_device_fops_release()
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 1136d7ac6b59..a2d34704f60f 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -778,7 +778,7 @@ static int vfio_pin_page_external(struct vfio_dma *dma, unsigned long vaddr,
if (ret == -ENOMEM)
pr_warn("%s: Task %s (%d) RLIMIT_MEMLOCK "
"(%ld) exceeded\n", __func__,
- dma->task->comm, task_pid_nr(dma->task),
+ dma->task->comm_str, task_pid_nr(dma->task),
task_rlimit(dma->task, RLIMIT_MEMLOCK));
}
}
diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c
index 5046cae05222..021e41bd7759 100644
--- a/drivers/vfio/vfio_main.c
+++ b/drivers/vfio/vfio_main.c
@@ -418,7 +418,7 @@ void vfio_unregister_group_dev(struct vfio_device *device)
"Device is currently in use, task"
" \"%s\" (%d) "
"blocked until device is released",
- current->comm, task_pid_nr(current));
+ current->comm_str, task_pid_nr(current));
}
}
}
diff --git a/drivers/xen/evtchn.c b/drivers/xen/evtchn.c
index 7e4a13e632dc..f51361e1e8e1 100644
--- a/drivers/xen/evtchn.c
+++ b/drivers/xen/evtchn.c
@@ -646,7 +646,7 @@ static int evtchn_open(struct inode *inode, struct file *filp)
if (u == NULL)
return -ENOMEM;
- u->name = kasprintf(GFP_KERNEL, "evtchn:%s", current->comm);
+ u->name = kasprintf(GFP_KERNEL, "evtchn:%s", current->comm_str);
if (u->name == NULL) {
kfree(u);
return -ENOMEM;
diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c
index 04a6b470b15d..6958ce227c4f 100644
--- a/drivers/xen/grant-table.c
+++ b/drivers/xen/grant-table.c
@@ -1163,7 +1163,7 @@ gnttab_retry_eagain_gop(unsigned int cmd, void *gop, int16_t *status,
} while ((*status == GNTST_eagain) && (delay < MAX_DELAY));
if (delay >= MAX_DELAY) {
- pr_err("%s: %s eagain grant\n", func, current->comm);
+ pr_err("%s: %s eagain grant\n", func, current->comm_str);
*status = GNTST_bad_page;
}
}
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index ea3e184cd2e3..e304d19c72e1 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -386,7 +386,7 @@ static unsigned long elf_map(struct file *filep, unsigned long addr,
if ((type & MAP_FIXED_NOREPLACE) &&
PTR_ERR((void *)map_addr) == -EEXIST)
pr_info("%d (%s): Uhuuh, elf segment at %px requested but the memory is mapped already\n",
- task_pid_nr(current), current->comm, (void *)addr);
+ task_pid_nr(current), current->comm_str, (void *)addr);
return(map_addr);
}
diff --git a/fs/coredump.c b/fs/coredump.c
index f88deb4701ac..0ea4bd2403a8 100644
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -200,7 +200,7 @@ static int cn_print_exe_file(struct core_name *cn, bool name_only)
exe_file = get_mm_exe_file(current->mm);
if (!exe_file)
- return cn_esc_printf(cn, "%s (path unknown)", current->comm);
+ return cn_esc_printf(cn, "%s (path unknown)", current->comm_str);
pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
if (!pathbuf) {
@@ -417,7 +417,7 @@ static bool coredump_parse(struct core_name *cn, struct coredump_params *cprm,
break;
/* executable, could be changed by prctl PR_SET_NAME etc */
case 'e':
- err = cn_esc_printf(cn, "%s", current->comm);
+ err = cn_esc_printf(cn, "%s", current->comm_str);
break;
/* file name of executable */
case 'f':
diff --git a/fs/drop_caches.c b/fs/drop_caches.c
index 019a8b4eaaf9..dbd3f2366028 100644
--- a/fs/drop_caches.c
+++ b/fs/drop_caches.c
@@ -70,7 +70,7 @@ static int drop_caches_sysctl_handler(const struct ctl_table *table, int write,
}
if (!stfu) {
pr_info("%s (%d): drop_caches: %d\n",
- current->comm, task_pid_nr(current),
+ current->comm_str, task_pid_nr(current),
sysctl_drop_caches);
}
stfu |= sysctl_drop_caches & 4;
diff --git a/fs/exec.c b/fs/exec.c
index 2a1e5e4042a1..80c92fadb367 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1082,11 +1082,11 @@ static int unshare_sighand(struct task_struct *me)
*/
void __set_task_comm(struct task_struct *tsk, const char *buf, bool exec)
{
- size_t len = min(strlen(buf), sizeof(tsk->comm) - 1);
+ size_t len = min(strlen(buf), sizeof(tsk->comm_str) - 1);
trace_task_rename(tsk, buf);
- memcpy(tsk->comm, buf, len);
- memset(&tsk->comm[len], 0, sizeof(tsk->comm) - len);
+ memcpy(tsk->comm_str, buf, len);
+ memset(&tsk->comm_str[len], 0, sizeof(tsk->comm_str) - len);
perf_event_comm(tsk, exec);
}
@@ -1854,7 +1854,7 @@ static int do_execveat_common(int fd, struct filename *filename,
bprm->argc = 1;
pr_warn_once("process '%s' launched '%s' with NULL argv: empty string added\n",
- current->comm, bprm->filename);
+ current->comm_str, bprm->filename);
}
retval = bprm_execve(bprm);
diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c
index d4164c507a90..5636a53b061e 100644
--- a/fs/ext4/dir.c
+++ b/fs/ext4/dir.c
@@ -537,7 +537,7 @@ static int call_filldir(struct file *file, struct dir_context *ctx,
if (!fname) {
ext4_msg(sb, KERN_ERR, "%s:%d: inode #%lu: comm %s: "
"called with null fname?!?", __func__, __LINE__,
- inode->i_ino, current->comm);
+ inode->i_ino, current->comm_str);
return 0;
}
ctx->pos = hash2pos(file, fname->hash, fname->minor_hash);
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 01c9b620b3f3..ed6743e660ce 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -5235,7 +5235,7 @@ struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
return ERR_PTR(-ESTALE);
__ext4_error(sb, function, line, false, EFSCORRUPTED, 0,
"inode #%lu: comm %s: iget: illegal inode #",
- ino, current->comm);
+ ino, current->comm_str);
return ERR_PTR(-EFSCORRUPTED);
}
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index a178ac229489..9e9c95e49587 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -147,7 +147,7 @@ static struct buffer_head *__ext4_read_dirblock(struct inode *inode,
"inode #%lu: lblock %lu: comm %s: "
"error %ld reading directory block",
inode->i_ino, (unsigned long)block,
- current->comm, PTR_ERR(bh));
+ current->comm_str, PTR_ERR(bh));
return bh;
}
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index d75b416401ae..a9e4e4898847 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -812,7 +812,7 @@ void __ext4_error(struct super_block *sb, const char *function,
vaf.va = &args;
printk(KERN_CRIT
"EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
- sb->s_id, function, line, current->comm, &vaf);
+ sb->s_id, function, line, current->comm_str, &vaf);
va_end(args);
}
fsnotify_sb_error(sb, NULL, error ? error : EFSCORRUPTED);
@@ -839,12 +839,12 @@ void __ext4_error_inode(struct inode *inode, const char *function,
printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
"inode #%lu: block %llu: comm %s: %pV\n",
inode->i_sb->s_id, function, line, inode->i_ino,
- block, current->comm, &vaf);
+ block, current->comm_str, &vaf);
else
printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
"inode #%lu: comm %s: %pV\n",
inode->i_sb->s_id, function, line, inode->i_ino,
- current->comm, &vaf);
+ current->comm_str, &vaf);
va_end(args);
}
fsnotify_sb_error(inode->i_sb, inode, error ? error : EFSCORRUPTED);
@@ -878,13 +878,13 @@ void __ext4_error_file(struct file *file, const char *function,
"EXT4-fs error (device %s): %s:%d: inode #%lu: "
"block %llu: comm %s: path %s: %pV\n",
inode->i_sb->s_id, function, line, inode->i_ino,
- block, current->comm, path, &vaf);
+ block, current->comm_str, path, &vaf);
else
printk(KERN_CRIT
"EXT4-fs error (device %s): %s:%d: inode #%lu: "
"comm %s: path %s: %pV\n",
inode->i_sb->s_id, function, line, inode->i_ino,
- current->comm, path, &vaf);
+ current->comm_str, path, &vaf);
va_end(args);
}
fsnotify_sb_error(inode->i_sb, inode, EFSCORRUPTED);
@@ -1022,7 +1022,7 @@ void __ext4_warning_inode(const struct inode *inode, const char *function,
vaf.va = &args;
printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
"inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
- function, line, inode->i_ino, current->comm, &vaf);
+ function, line, inode->i_ino, current->comm_str, &vaf);
va_end(args);
}
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 14929fcea52d..d4263c3da019 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -1540,7 +1540,7 @@ struct file *hugetlb_file_setup(const char *name, size_t size,
if (user_shm_lock(size, ucounts)) {
pr_warn_once("%s (%d): Using mlock ulimits for SHM_HUGETLB is obsolete\n",
- current->comm, current->pid);
+ current->comm_str, current->pid);
user_shm_unlock(size, ucounts);
}
return ERR_PTR(-EPERM);
diff --git a/fs/ioctl.c b/fs/ioctl.c
index 0248cb8db2d3..3c543b581501 100644
--- a/fs/ioctl.c
+++ b/fs/ioctl.c
@@ -79,7 +79,7 @@ static int ioctl_fibmap(struct file *filp, int __user *p)
if (block > INT_MAX) {
error = -ERANGE;
pr_warn_ratelimited("[%s/%d] FS: %s File: %pD4 would truncate fibmap result\n",
- current->comm, task_pid_nr(current),
+ current->comm_str, task_pid_nr(current),
sb->s_id, filp);
}
diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
index 844261a31156..231a1a904496 100644
--- a/fs/iomap/direct-io.c
+++ b/fs/iomap/direct-io.c
@@ -570,7 +570,7 @@ static int iomap_dio_iter(struct iomap_iter *iter, struct iomap_dio *dio)
* DELALLOC block that the page-mkwrite allocated.
*/
pr_warn_ratelimited("Direct I/O collision with buffered writes! File: %pD4 Comm: %.20s\n",
- dio->iocb->ki_filp, current->comm);
+ dio->iocb->ki_filp, current->comm_str);
return -EIO;
default:
WARN_ON_ONCE(1);
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index c7867139af69..800c5aa86d49 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -329,7 +329,7 @@ static int start_this_handle(journal_t *journal, handle_t *handle,
rsv_blocks + blocks > jbd2_max_user_trans_buffers(journal)) {
printk(KERN_ERR "JBD2: %s wants too many credits "
"credits:%d rsv_credits:%d max:%d\n",
- current->comm, blocks, rsv_blocks,
+ current->comm_str, blocks, rsv_blocks,
jbd2_max_user_trans_buffers(journal));
WARN_ON(1);
return -ENOSPC;
diff --git a/fs/locks.c b/fs/locks.c
index 559f02aa4172..ba204c8b2316 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -2146,7 +2146,7 @@ SYSCALL_DEFINE2(flock, unsigned int, fd, unsigned int, cmd)
* throw a warning to let people know that they don't actually work.
*/
if (cmd & LOCK_MAND) {
- pr_warn_once("%s(%d): Attempt to set a LOCK_MAND lock via flock(2). This support has been removed and the request ignored.\n", current->comm, current->pid);
+ pr_warn_once("%s(%d): Attempt to set a LOCK_MAND lock via flock(2). This support has been removed and the request ignored.\n", current->comm_str, current->pid);
return 0;
}
diff --git a/fs/netfs/internal.h b/fs/netfs/internal.h
index d4f16fefd965..2988d5cf3c88 100644
--- a/fs/netfs/internal.h
+++ b/fs/netfs/internal.h
@@ -443,7 +443,7 @@ void fscache_create_volume(struct fscache_volume *volume, bool wait);
* debug tracing
*/
#define dbgprintk(FMT, ...) \
- printk("[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
+ printk("[%-6.6s] "FMT"\n", current->comm_str, ##__VA_ARGS__)
#define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
#define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
diff --git a/fs/proc/base.c b/fs/proc/base.c
index e93149a01341..7f05e8b8f09a 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1144,7 +1144,7 @@ static int __set_oom_adj(struct file *file, int oom_adj, bool legacy)
* /proc/pid/oom_score_adj instead.
*/
pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n",
- current->comm, task_pid_nr(current), task_pid_nr(task),
+ current->comm_str, task_pid_nr(current), task_pid_nr(task),
task_pid_nr(task));
} else {
if ((short)oom_adj < task->signal->oom_score_adj_min &&
diff --git a/fs/read_write.c b/fs/read_write.c
index c5b6265d984b..5cb15fa8a3ed 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -499,7 +499,7 @@ static int warn_unsupported(struct file *file, const char *op)
{
pr_warn_ratelimited(
"kernel %s not supported for file %pD4 (pid: %d comm: %.20s)\n",
- op, file, current->pid, current->comm);
+ op, file, current->pid, current->comm_str);
return -EINVAL;
}
diff --git a/fs/splice.c b/fs/splice.c
index 4d6df083e0c0..b02395d5921f 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -920,7 +920,7 @@ static int warn_unsupported(struct file *file, const char *op)
{
pr_debug_ratelimited(
"splice %s not supported for file %pD4 (pid: %d comm: %.20s)\n",
- op, file, current->pid, current->comm);
+ op, file, current->pid, current->comm_str);
return -EINVAL;
}
diff --git a/include/linux/coredump.h b/include/linux/coredump.h
index 988b233dcc09..a53e5fe41b05 100644
--- a/include/linux/coredump.h
+++ b/include/linux/coredump.h
@@ -54,7 +54,7 @@ extern void vfs_coredump(const kernel_siginfo_t *siginfo);
do { \
char comm[TASK_COMM_LEN]; \
/* This will always be NUL terminated. */ \
- memcpy(comm, current->comm, TASK_COMM_LEN); \
+ memcpy(comm, current->comm_str, TASK_COMM_LEN); \
comm[TASK_COMM_LEN - 1] = '\0'; \
printk_ratelimited(Level "coredump: %d(%*pE): " Format "\n", \
task_tgid_vnr(current), (int)strlen(comm), comm, ##__VA_ARGS__); \
diff --git a/include/linux/filter.h b/include/linux/filter.h
index eca229752cbe..2ae63a4c54c8 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -1285,7 +1285,7 @@ static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
u32 pass, void *image)
{
pr_err("flen=%u proglen=%u pass=%u image=%pK from=%s pid=%d\n", flen,
- proglen, pass, image, current->comm, task_pid_nr(current));
+ proglen, pass, image, current->comm_str, task_pid_nr(current));
if (image)
print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET,
diff --git a/include/linux/ratelimit.h b/include/linux/ratelimit.h
index 7aaad158ee37..751cd81867ef 100644
--- a/include/linux/ratelimit.h
+++ b/include/linux/ratelimit.h
@@ -58,7 +58,7 @@ static inline void ratelimit_state_exit(struct ratelimit_state *rs)
m = ratelimit_state_reset_miss(rs);
if (m)
- pr_warn("%s: %d output lines suppressed due to ratelimiting\n", current->comm, m);
+ pr_warn("%s: %d output lines suppressed due to ratelimiting\n", current->comm_str, m);
}
static inline void
diff --git a/include/linux/sched.h b/include/linux/sched.h
index a4a23267a982..1cdfb024173e 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -316,6 +316,7 @@ struct user_event_mm;
*/
enum {
TASK_COMM_LEN = 16,
+ TASK_COMM_EXT_LEN = 64,
};
extern void sched_tick(void);
@@ -1158,7 +1159,7 @@ struct task_struct {
* - logic inside set_task_comm() will ensure it is always NUL-terminated and
* zero-padded
*/
- char comm[TASK_COMM_LEN];
+ char comm_str[TASK_COMM_EXT_LEN];
struct nameidata *nameidata;
@@ -1941,7 +1942,7 @@ extern void kick_process(struct task_struct *tsk);
extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
#define set_task_comm(tsk, from) ({ \
- BUILD_BUG_ON(sizeof(from) != TASK_COMM_LEN); \
+ BUILD_BUG_ON(sizeof(from) < TASK_COMM_LEN); \
__set_task_comm(tsk, from, false); \
})
@@ -1960,7 +1961,11 @@ extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec
*/
#define get_task_comm(buf, tsk) ({ \
BUILD_BUG_ON(sizeof(buf) < TASK_COMM_LEN); \
- strscpy_pad(buf, (tsk)->comm); \
+ strscpy_pad(buf, (tsk)->comm_str); \
+ if ((sizeof(buf)) == TASK_COMM_LEN) \
+ buf[TASK_COMM_LEN - 1] = '\0'; \
+ else \
+ buf[TASK_COMM_EXT_LEN - 1] = '\0'; \
buf; \
})
diff --git a/init/init_task.c b/init/init_task.c
index e557f622bd90..afb815189efc 100644
--- a/init/init_task.c
+++ b/init/init_task.c
@@ -121,7 +121,7 @@ struct task_struct init_task __aligned(L1_CACHE_BYTES) = {
.group_leader = &init_task,
RCU_POINTER_INITIALIZER(real_cred, &init_cred),
RCU_POINTER_INITIALIZER(cred, &init_cred),
- .comm = INIT_TASK_COMM,
+ .comm_str = INIT_TASK_COMM,
.thread = INIT_THREAD,
.fs = &init_fs,
.files = &init_files,
diff --git a/ipc/sem.c b/ipc/sem.c
index a39cdc7bf88f..764d03a43f6c 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -1083,7 +1083,7 @@ static int check_qop(struct sem_array *sma, int semnum, struct sem_queue *q,
*/
pr_info_once("semctl(GETNCNT/GETZCNT) is since 3.16 Single Unix Specification compliant.\n"
"The task %s (%d) triggered the difference, watch for misbehavior.\n",
- current->comm, task_pid_nr(current));
+ current->comm_str, task_pid_nr(current));
if (sop->sem_num != semnum)
return 0;
diff --git a/kernel/acct.c b/kernel/acct.c
index 6520baa13669..2e4a029d97c9 100644
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -481,7 +481,7 @@ static void fill_ac(struct bsd_acct_struct *acct)
memset(ac, 0, sizeof(acct_t));
ac->ac_version = ACCT_VERSION | ACCT_BYTEORDER;
- strscpy(ac->ac_comm, current->comm, sizeof(ac->ac_comm));
+ strscpy(ac->ac_comm, current->comm_str, sizeof(ac->ac_comm));
/* calculate run_time in nsec*/
run_time = ktime_get_ns();
diff --git a/kernel/audit.c b/kernel/audit.c
index 61b5744d0bb6..cdead92ab251 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -1600,7 +1600,7 @@ static void audit_log_multicast(int group, const char *op, int err)
{
const struct cred *cred;
struct tty_struct *tty;
- char comm[sizeof(current->comm)];
+ char comm[sizeof(current->comm_str)];
struct audit_buffer *ab;
if (!audit_enabled)
@@ -2243,7 +2243,7 @@ void audit_put_tty(struct tty_struct *tty)
void audit_log_task_info(struct audit_buffer *ab)
{
const struct cred *cred;
- char comm[sizeof(current->comm)];
+ char comm[sizeof(current->comm_str)];
struct tty_struct *tty;
if (!ab)
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index eb98cd6fe91f..89e7e972049e 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -2723,7 +2723,7 @@ void __audit_ptrace(struct task_struct *t)
context->target_auid = audit_get_loginuid(t);
context->target_uid = task_uid(t);
context->target_sessionid = audit_get_sessionid(t);
- strscpy(context->target_comm, t->comm);
+ strscpy(context->target_comm, t->comm_str);
security_task_getlsmprop_obj(t, &context->target_ref);
}
@@ -2750,7 +2750,7 @@ int audit_signal_info_syscall(struct task_struct *t)
ctx->target_auid = audit_get_loginuid(t);
ctx->target_uid = t_uid;
ctx->target_sessionid = audit_get_sessionid(t);
- strscpy(ctx->target_comm, t->comm);
+ strscpy(ctx->target_comm, t->comm_str);
security_task_getlsmprop_obj(t, &ctx->target_ref);
return 0;
}
@@ -2772,7 +2772,7 @@ int audit_signal_info_syscall(struct task_struct *t)
axp->target_uid[axp->pid_count] = t_uid;
axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
security_task_getlsmprop_obj(t, &axp->target_ref[axp->pid_count]);
- strscpy(axp->target_comm[axp->pid_count], t->comm);
+ strscpy(axp->target_comm[axp->pid_count], t->comm_str);
axp->pid_count++;
return 0;
@@ -2919,7 +2919,7 @@ void __audit_log_nfcfg(const char *name, u8 af, unsigned int nentries,
enum audit_nfcfgop op, gfp_t gfp)
{
struct audit_buffer *ab;
- char comm[sizeof(current->comm)];
+ char comm[sizeof(current->comm_str)];
ab = audit_log_start(audit_context(), gfp, AUDIT_NETFILTER_CFG);
if (!ab)
@@ -2940,7 +2940,7 @@ static void audit_log_task(struct audit_buffer *ab)
kuid_t auid, uid;
kgid_t gid;
unsigned int sessionid;
- char comm[sizeof(current->comm)];
+ char comm[sizeof(current->comm_str)];
auid = audit_get_loginuid(current);
sessionid = audit_get_sessionid(current);
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index 6b4877e85a68..9c3e48f1348f 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -266,7 +266,7 @@ BPF_CALL_2(bpf_get_current_comm, char *, buf, u32, size)
goto err_clear;
/* Verifier guarantees that size > 0 */
- strscpy_pad(buf, task->comm, size);
+ strscpy_pad(buf, task->comm_str, size);
return 0;
err_clear:
memset(buf, 0, size);
diff --git a/kernel/capability.c b/kernel/capability.c
index 829f49ae07b9..73f945dadb58 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -39,7 +39,7 @@ __setup("no_file_caps", file_caps_disable);
static void warn_legacy_capability_use(void)
{
pr_info_once("warning: `%s' uses 32-bit capabilities (legacy support in use)\n",
- current->comm);
+ current->comm_str);
}
/*
@@ -61,7 +61,7 @@ static void warn_legacy_capability_use(void)
static void warn_deprecated_v2(void)
{
pr_info_once("warning: `%s' uses deprecated v2 capabilities in a way that may be insecure\n",
- current->comm);
+ current->comm_str);
}
/*
diff --git a/kernel/cgroup/cgroup-v1.c b/kernel/cgroup/cgroup-v1.c
index fa24c032ed6f..05e6a54d710f 100644
--- a/kernel/cgroup/cgroup-v1.c
+++ b/kernel/cgroup/cgroup-v1.c
@@ -1101,7 +1101,7 @@ int cgroup1_reconfigure(struct fs_context *fc)
if (ctx->subsys_mask != root->subsys_mask || ctx->release_agent)
pr_warn("option changes via remount are deprecated (pid=%d comm=%s)\n",
- task_tgid_nr(current), current->comm);
+ task_tgid_nr(current), current->comm_str);
added_mask = ctx->subsys_mask & ~root->subsys_mask;
removed_mask = root->subsys_mask & ~ctx->subsys_mask;
diff --git a/kernel/cred.c b/kernel/cred.c
index 9676965c0981..2e5e9a60aee0 100644
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -23,13 +23,13 @@
#if 0
#define kdebug(FMT, ...) \
printk("[%-5.5s%5u] " FMT "\n", \
- current->comm, current->pid, ##__VA_ARGS__)
+ current->comm_str, current->pid, ##__VA_ARGS__)
#else
#define kdebug(FMT, ...) \
do { \
if (0) \
no_printk("[%-5.5s%5u] " FMT "\n", \
- current->comm, current->pid, ##__VA_ARGS__); \
+ current->comm_str, current->pid, ##__VA_ARGS__); \
} while (0)
#endif
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 22fdf0c187cd..e39c8556685a 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8962,7 +8962,7 @@ static void perf_event_comm_event(struct perf_comm_event *comm_event)
unsigned int size;
memset(comm, 0, sizeof(comm));
- strscpy(comm, comm_event->task->comm);
+ strscpy(comm, comm_event->task->comm_str);
size = ALIGN(strlen(comm)+1, sizeof(u64));
comm_event->comm = comm;
diff --git a/kernel/exit.c b/kernel/exit.c
index f03caf17b214..198227a39eb9 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -850,7 +850,7 @@ static void check_stack_usage(void)
spin_lock(&low_water_lock);
if (free < lowest_to_date) {
pr_info("%s (%d) used greatest stack depth: %lu bytes left\n",
- current->comm, task_pid_nr(current), free);
+ current->comm_str, task_pid_nr(current), free);
lowest_to_date = free;
}
spin_unlock(&low_water_lock);
@@ -1023,12 +1023,12 @@ void __noreturn make_task_dead(int signr)
if (unlikely(irqs_disabled())) {
pr_info("note: %s[%d] exited with irqs disabled\n",
- current->comm, task_pid_nr(current));
+ current->comm_str, task_pid_nr(current));
local_irq_enable();
}
if (unlikely(in_atomic())) {
pr_info("note: %s[%d] exited with preempt_count %d\n",
- current->comm, task_pid_nr(current),
+ current->comm_str, task_pid_nr(current),
preempt_count());
preempt_count_set(PREEMPT_ENABLED);
}
diff --git a/kernel/fork.c b/kernel/fork.c
index cfe2f1df5f27..fd5bb94596ba 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1922,6 +1922,7 @@ __latent_entropy struct task_struct *copy_process(
struct file *pidfile = NULL;
const u64 clone_flags = args->flags;
struct nsproxy *nsp = current->nsproxy;
+ unsigned char comm[TASK_COMM_EXT_LEN];
/*
* Don't allow sharing the root directory with processes in a different
@@ -2013,8 +2014,12 @@ __latent_entropy struct task_struct *copy_process(
if (args->io_thread)
p->flags |= PF_IO_WORKER;
- if (args->name)
- strscpy_pad(p->comm, args->name, sizeof(p->comm));
+ if (args->name) {
+ memcpy(comm, args->name, sizeof(p->comm_str) - 1);
+ comm[sizeof(p->comm_str) - 1] = '\0';
+
+ set_task_comm(p, comm);
+ }
p->set_child_tid = (clone_flags & CLONE_CHILD_SETTID) ? args->child_tid : NULL;
/*
diff --git a/kernel/freezer.c b/kernel/freezer.c
index 8d530d0949ff..e5b066b7a166 100644
--- a/kernel/freezer.c
+++ b/kernel/freezer.c
@@ -64,7 +64,7 @@ bool __refrigerator(bool check_kthr_stop)
unsigned int state = get_current_state();
bool was_frozen = false;
- pr_debug("%s entered refrigerator\n", current->comm);
+ pr_debug("%s entered refrigerator\n", current->comm_str);
WARN_ON_ONCE(state && !(state & TASK_NORMAL));
@@ -89,7 +89,7 @@ bool __refrigerator(bool check_kthr_stop)
}
__set_current_state(TASK_RUNNING);
- pr_debug("%s left refrigerator\n", current->comm);
+ pr_debug("%s left refrigerator\n", current->comm_str);
return was_frozen;
}
diff --git a/kernel/futex/waitwake.c b/kernel/futex/waitwake.c
index e2bbe5509ec2..d72246096c06 100644
--- a/kernel/futex/waitwake.c
+++ b/kernel/futex/waitwake.c
@@ -214,7 +214,7 @@ static int futex_atomic_op_inuser(unsigned int encoded_op, u32 __user *uaddr)
* is sane again
*/
pr_info_ratelimited("futex_wake_op: %s tries to shift op by %d; fix this program\n",
- current->comm, oparg);
+ current->comm_str, oparg);
oparg &= 31;
}
oparg = 1 << oparg;
diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index 8708a1205f82..470ad5bdfc47 100644
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c
@@ -138,11 +138,11 @@ static void debug_show_blocker(struct task_struct *task)
switch (blocker_type) {
case BLOCKER_TYPE_MUTEX:
pr_err("INFO: task %s:%d is blocked on a mutex, but the owner is not found.\n",
- task->comm, task->pid);
+ task->comm_str, task->pid);
break;
case BLOCKER_TYPE_SEM:
pr_err("INFO: task %s:%d is blocked on a semaphore, but the last holder is not found.\n",
- task->comm, task->pid);
+ task->comm_str, task->pid);
break;
case BLOCKER_TYPE_RWSEM_READER:
case BLOCKER_TYPE_RWSEM_WRITER:
@@ -161,11 +161,11 @@ static void debug_show_blocker(struct task_struct *task)
switch (blocker_type) {
case BLOCKER_TYPE_MUTEX:
pr_err("INFO: task %s:%d is blocked on a mutex likely owned by task %s:%d.\n",
- task->comm, task->pid, t->comm, t->pid);
+ task->comm_str, task->pid, t->comm_str, t->pid);
break;
case BLOCKER_TYPE_SEM:
pr_err("INFO: task %s:%d blocked on a semaphore likely last held by task %s:%d\n",
- task->comm, task->pid, t->comm, t->pid);
+ task->comm_str, task->pid, t->comm_str, t->pid);
break;
case BLOCKER_TYPE_RWSEM_READER:
case BLOCKER_TYPE_RWSEM_WRITER:
@@ -233,7 +233,7 @@ static void check_hung_task(struct task_struct *t, unsigned long timeout)
if (sysctl_hung_task_warnings > 0)
sysctl_hung_task_warnings--;
pr_err("INFO: task %s:%d blocked for more than %ld seconds.\n",
- t->comm, t->pid, (jiffies - t->last_switch_time) / HZ);
+ t->comm_str, t->pid, (jiffies - t->last_switch_time) / HZ);
pr_err(" %s %s %.*s\n",
print_tainted(), init_utsname()->release,
(int)strcspn(init_utsname()->version, " "),
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index c94837382037..6f52730f86e4 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -1175,7 +1175,7 @@ static void irq_thread_dtor(struct callback_head *unused)
action = kthread_data(tsk);
pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
- tsk->comm, tsk->pid, action->irq);
+ tsk->comm_str, tsk->pid, action->irq);
desc = irq_to_desc(action->irq);
diff --git a/kernel/kthread.c b/kernel/kthread.c
index 0e98b228a8ef..4222e531d487 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -108,7 +108,7 @@ void get_kthread_comm(char *buf, size_t buf_size, struct task_struct *tsk)
struct kthread *kthread = to_kthread(tsk);
if (!kthread || !kthread->full_name) {
- strscpy(buf, tsk->comm, buf_size);
+ strscpy(buf, tsk->comm_str, buf_size);
return;
}
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index c80902eacd79..ab883220d4e8 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -712,7 +712,7 @@ static int __sched rt_mutex_adjust_prio_chain(struct task_struct *task,
prev_max = max_lock_depth;
printk(KERN_WARNING "Maximum lock depth %d reached "
"task: %s (%d)\n", max_lock_depth,
- top_task->comm, task_pid_nr(top_task));
+ top_task->comm_str, task_pid_nr(top_task));
}
put_task_struct(task);
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 0efbcdda9aab..ba7f690c8ba9 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -777,7 +777,7 @@ static ssize_t devkmsg_write(struct kiocb *iocb, struct iov_iter *from)
/* Ratelimit when not explicitly enabled. */
if (!(devkmsg_log & DEVKMSG_LOG_MASK_ON)) {
- if (!___ratelimit(&user->rs, current->comm))
+ if (!___ratelimit(&user->rs, current->comm_str))
return ret;
}
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index ae360daf7d80..c4c437b1a035 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -3240,7 +3240,7 @@ void force_compatible_cpus_allowed_ptr(struct task_struct *p)
out_set_mask:
if (printk_ratelimit()) {
printk_deferred("Overriding affinity for process %d (%s) to CPUs %*pbl\n",
- task_pid_nr(p), p->comm,
+ task_pid_nr(p), p->comm_str,
cpumask_pr_args(override_mask));
}
@@ -3545,7 +3545,7 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
*/
if (p->mm && printk_ratelimit()) {
printk_deferred("process %d (%s) no longer affine to cpu%d\n",
- task_pid_nr(p), p->comm, cpu);
+ task_pid_nr(p), p->comm_str, cpu);
}
}
@@ -5156,7 +5156,7 @@ static struct rq *finish_task_switch(struct task_struct *prev)
*/
if (WARN_ONCE(preempt_count() != 2*PREEMPT_DISABLE_OFFSET,
"corrupted preempt_count: %s/%d/0x%x\n",
- current->comm, current->pid, preempt_count()))
+ current->comm_str, current->pid, preempt_count()))
preempt_count_set(FORK_PREEMPT_COUNT);
rq->prev_mm = NULL;
@@ -5849,7 +5849,7 @@ static noinline void __schedule_bug(struct task_struct *prev)
return;
printk(KERN_ERR "BUG: scheduling while atomic: %s/%d/0x%08x\n",
- prev->comm, prev->pid, preempt_count());
+ prev->comm_str, prev->pid, preempt_count());
debug_show_held_locks(prev);
print_modules();
@@ -5881,7 +5881,7 @@ static inline void schedule_debug(struct task_struct *prev, bool preempt)
#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
if (!preempt && READ_ONCE(prev->__state) && prev->non_block_count) {
printk(KERN_ERR "BUG: scheduling in a non-blocking section: %s/%d/%i\n",
- prev->comm, prev->pid, prev->non_block_count);
+ prev->comm_str, prev->pid, prev->non_block_count);
dump_stack();
add_taint(TAINT_WARN, LOCKDEP_STILL_OK);
}
@@ -7645,7 +7645,7 @@ void sched_show_task(struct task_struct *p)
if (!try_get_task_stack(p))
return;
- pr_info("task:%-15.15s state:%c", p->comm, task_state_to_char(p));
+ pr_info("task:%-15.15s state:%c", p->comm_str, task_state_to_char(p));
if (task_is_running(p))
pr_cont(" running task ");
@@ -7786,7 +7786,7 @@ void __init init_idle(struct task_struct *idle, int cpu)
idle->sched_class = &idle_sched_class;
ftrace_graph_init_idle_task(idle, cpu);
vtime_init_idle(idle, cpu);
- sprintf(idle->comm, "%s/%d", INIT_TASK_COMM, cpu);
+ sprintf(idle->comm_str, "%s/%d", INIT_TASK_COMM, cpu);
}
int cpuset_cpumask_can_shrink(const struct cpumask *cur,
@@ -8322,7 +8322,7 @@ static void dump_rq_tasks(struct rq *rq, const char *loglvl)
if (!task_on_rq_queued(p))
continue;
- printk("%s\tpid: %d, name: %s\n", loglvl, p->pid, p->comm);
+ printk("%s\tpid: %d, name: %s\n", loglvl, p->pid, p->comm_str);
}
}
@@ -8667,7 +8667,7 @@ void __might_resched(const char *file, int line, unsigned int offsets)
file, line);
pr_err("in_atomic(): %d, irqs_disabled(): %d, non_block: %d, pid: %d, name: %s\n",
in_atomic(), irqs_disabled(), current->non_block_count,
- current->pid, current->comm);
+ current->pid, current->comm_str);
pr_err("preempt_count: %x, expected: %x\n", preempt_count(),
offsets & MIGHT_RESCHED_PREEMPT_MASK);
@@ -8711,7 +8711,7 @@ void __cant_sleep(const char *file, int line, int preempt_offset)
printk(KERN_ERR "BUG: assuming atomic context at %s:%d\n", file, line);
printk(KERN_ERR "in_atomic(): %d, irqs_disabled(): %d, pid: %d, name: %s\n",
in_atomic(), irqs_disabled(),
- current->pid, current->comm);
+ current->pid, current->comm_str);
debug_show_held_locks(current);
dump_stack();
@@ -8743,7 +8743,7 @@ void __cant_migrate(const char *file, int line)
pr_err("BUG: assuming non migratable context at %s:%d\n", file, line);
pr_err("in_atomic(): %d, irqs_disabled(): %d, migration_disabled() %u pid: %d, name: %s\n",
in_atomic(), irqs_disabled(), is_migration_disabled(current),
- current->pid, current->comm);
+ current->pid, current->comm_str);
debug_show_held_locks(current);
dump_stack();
diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index 3f06ab84d53f..24db33d9016e 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -734,7 +734,7 @@ print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
SEQ_printf(m, " %c", task_state_to_char(p));
SEQ_printf(m, " %15s %5d %9Ld.%06ld %c %9Ld.%06ld %c %9Ld.%06ld %9Ld.%06ld %9Ld %5d ",
- p->comm, task_pid_nr(p),
+ p->comm_str, task_pid_nr(p),
SPLIT_NS(p->se.vruntime),
entity_eligible(cfs_rq_of(&p->se), &p->se) ? 'E' : 'N',
SPLIT_NS(p->se.deadline),
@@ -1150,7 +1150,7 @@ void proc_sched_show_task(struct task_struct *p, struct pid_namespace *ns,
{
unsigned long nr_switches;
- SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, task_pid_nr_ns(p, ns),
+ SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm_str, task_pid_nr_ns(p, ns),
get_nr_threads(p));
SEQ_printf(m,
"---------------------------------------------------------"
diff --git a/kernel/signal.c b/kernel/signal.c
index e2c928de7d2c..de0e1a413d04 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -257,7 +257,7 @@ static inline void print_dropped_signal(int sig)
return;
pr_info("%s/%d: reached RLIMIT_SIGPENDING, dropped signal %d\n",
- current->comm, current->pid, sig);
+ current->comm_str, current->pid, sig);
}
/**
@@ -1224,11 +1224,11 @@ static void print_fatal_signal(int signr)
exe_file = get_task_exe_file(current);
if (exe_file) {
pr_info("%pD: %s: potentially unexpected fatal signal %d.\n",
- exe_file, current->comm, signr);
+ exe_file, current->comm_str, signr);
fput(exe_file);
} else {
pr_info("%s: potentially unexpected fatal signal %d.\n",
- current->comm, signr);
+ current->comm_str, signr);
}
#if defined(__i386__) && !defined(__arch_um__)
diff --git a/kernel/sys.c b/kernel/sys.c
index 1e28b40053ce..25c79f78fbbf 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -2456,7 +2456,7 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
unsigned long, arg4, unsigned long, arg5)
{
struct task_struct *me = current;
- unsigned char comm[sizeof(me->comm)];
+ unsigned char comm[sizeof(me->comm_str)];
long error;
error = security_task_prctl(option, arg2, arg3, arg4, arg5);
@@ -2512,9 +2512,9 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
error = -EINVAL;
break;
case PR_SET_NAME:
- comm[sizeof(me->comm) - 1] = 0;
+ comm[sizeof(me->comm_str) - 1] = 0;
if (strncpy_from_user(comm, (char __user *)arg2,
- sizeof(me->comm) - 1) < 0)
+ sizeof(me->comm_str) - 1) < 0)
return -EFAULT;
set_task_comm(me, comm);
proc_comm_connector(me);
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index cb6196e3fa99..e5bceda6fc3d 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -140,7 +140,7 @@ static void warn_sysctl_write(const struct ctl_table *table)
pr_warn_once("%s wrote to %s when file position was not 0!\n"
"This will not be supported in the future. To silence this\n"
"warning, set kernel.sysctl_writes_strict = -1\n",
- current->comm, table->procname);
+ current->comm_str, table->procname);
}
/**
diff --git a/kernel/time/itimer.c b/kernel/time/itimer.c
index 876d389b2e21..7fda10130508 100644
--- a/kernel/time/itimer.c
+++ b/kernel/time/itimer.c
@@ -363,7 +363,7 @@ SYSCALL_DEFINE3(setitimer, int, which, struct __kernel_old_itimerval __user *, v
memset(&set_buffer, 0, sizeof(set_buffer));
printk_once(KERN_WARNING "%s calls setitimer() with new_value NULL pointer."
" Misfeature support will be removed\n",
- current->comm);
+ current->comm_str);
}
error = do_setitimer(which, &set_buffer, ovalue ? &get_buffer : NULL);
@@ -410,7 +410,7 @@ COMPAT_SYSCALL_DEFINE3(setitimer, int, which,
memset(&set_buffer, 0, sizeof(set_buffer));
printk_once(KERN_WARNING "%s calls setitimer() with new_value NULL pointer."
" Misfeature support will be removed\n",
- current->comm);
+ current->comm_str);
}
error = do_setitimer(which, &set_buffer, ovalue ? &get_buffer : NULL);
diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index 2e5b89d7d866..19ed72294481 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -851,7 +851,7 @@ static bool check_rlimit(u64 time, u64 limit, int signo, bool rt, bool hard)
if (print_fatal_signals) {
pr_info("%s Watchdog Timeout (%s): %s[%d]\n",
rt ? "RT" : "CPU", hard ? "hard" : "soft",
- current->comm, task_pid_nr(current));
+ current->comm_str, task_pid_nr(current));
}
send_signal_locked(signo, SEND_SIG_PRIV, current, PIDTYPE_TGID);
return true;
diff --git a/kernel/tsacct.c b/kernel/tsacct.c
index 16b283f9d831..6eaa5e0e20b4 100644
--- a/kernel/tsacct.c
+++ b/kernel/tsacct.c
@@ -76,7 +76,7 @@ void bacct_add_tsk(struct user_namespace *user_ns,
stats->ac_minflt = tsk->min_flt;
stats->ac_majflt = tsk->maj_flt;
- strscpy_pad(stats->ac_comm, tsk->comm);
+ strscpy_pad(stats->ac_comm, tsk->comm_str);
}
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index ae99311f1a96..a573cd6b26b3 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -3252,7 +3252,7 @@ __acquires(&pool->lock)
rcu_preempt_depth() != rcu_start_depth)) {
pr_err("BUG: workqueue leaked atomic, lock or RCU: %s[%d]\n"
" preempt=0x%08x lock=%d->%d RCU=%d->%d workfn=%ps\n",
- current->comm, task_pid_nr(current), preempt_count(),
+ current->comm_str, task_pid_nr(current), preempt_count(),
lockdep_start_depth, lockdep_depth(current),
rcu_start_depth, rcu_preempt_depth(),
worker->current_func);
@@ -3716,7 +3716,7 @@ static void check_flush_dependency(struct workqueue_struct *target_wq,
WARN_ONCE(current->flags & PF_MEMALLOC,
"workqueue: PF_MEMALLOC task %d(%s) is flushing !WQ_MEM_RECLAIM %s:%ps",
- current->pid, current->comm, target_wq->name, target_func);
+ current->pid, current->comm_str, target_wq->name, target_func);
WARN_ONCE(worker && ((worker->current_pwq->wq->flags &
(WQ_MEM_RECLAIM | __WQ_LEGACY)) == WQ_MEM_RECLAIM),
"workqueue: WQ_MEM_RECLAIM %s:%ps is flushing !WQ_MEM_RECLAIM %s:%ps",
@@ -6486,7 +6486,7 @@ void wq_worker_comm(char *buf, size_t size, struct task_struct *task)
raw_spin_unlock_irq(&pool->lock);
}
} else {
- strscpy(buf, task->comm, size);
+ strscpy(buf, task->comm_str, size);
}
mutex_unlock(&wq_pool_attach_mutex);
diff --git a/lib/dump_stack.c b/lib/dump_stack.c
index b3a85fe8b673..5ebf7503f3c6 100644
--- a/lib/dump_stack.c
+++ b/lib/dump_stack.c
@@ -57,7 +57,7 @@ void dump_stack_print_info(const char *log_lvl)
printk("%sCPU: %d UID: %u PID: %d Comm: %.20s %s%s %s %.*s %s " BUILD_ID_FMT "\n",
log_lvl, raw_smp_processor_id(),
__kuid_val(current_real_cred()->euid),
- current->pid, current->comm,
+ current->pid, current->comm_str,
kexec_crash_loaded() ? "Kdump: loaded " : "",
print_tainted(),
init_utsname()->release,
diff --git a/lib/nlattr.c b/lib/nlattr.c
index be9c576b6e2d..994a4ae5b2ec 100644
--- a/lib/nlattr.c
+++ b/lib/nlattr.c
@@ -212,7 +212,7 @@ static int nla_validate_range_unsigned(const struct nla_policy *pt,
if (pt->validation_type == NLA_VALIDATE_RANGE_WARN_TOO_LONG &&
pt->type == NLA_BINARY && value > range.max) {
pr_warn_ratelimited("netlink: '%s': attribute type %d has an invalid length.\n",
- current->comm, pt->type);
+ current->comm_str, pt->type);
if (validate & NL_VALIDATE_STRICT_ATTRS) {
NL_SET_ERR_MSG_ATTR_POL(extack, nla, pt,
"invalid attribute length");
@@ -412,7 +412,7 @@ static int validate_nla(const struct nlattr *nla, int maxtype,
if (nla_attr_len[pt->type] && attrlen != nla_attr_len[pt->type]) {
pr_warn_ratelimited("netlink: '%s': attribute type %d has an invalid length.\n",
- current->comm, type);
+ current->comm_str, type);
if (validate & NL_VALIDATE_STRICT_ATTRS) {
NL_SET_ERR_MSG_ATTR_POL(extack, nla, pt,
"invalid attribute length");
@@ -645,7 +645,7 @@ static int __nla_validate_parse(const struct nlattr *head, int len, int maxtype,
if (unlikely(rem > 0)) {
pr_warn_ratelimited("netlink: %d bytes leftover after parsing attributes in process `%s'.\n",
- rem, current->comm);
+ rem, current->comm_str);
NL_SET_ERR_MSG(extack, "bytes leftover after parsing attributes");
if (validate & NL_VALIDATE_TRAILING)
return -EINVAL;
diff --git a/mm/compaction.c b/mm/compaction.c
index bf021b31c7ec..e89741a68834 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -3278,7 +3278,7 @@ static int proc_dointvec_minmax_warn_RT_change(const struct ctl_table *table,
return ret;
if (old != *(int *)table->data)
pr_warn_once("sysctl attribute %s changed by %s[%d]\n",
- table->procname, current->comm,
+ table->procname, current->comm_str,
task_pid_nr(current));
return ret;
}
diff --git a/mm/filemap.c b/mm/filemap.c
index 413492492b5a..085335253b11 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -154,7 +154,7 @@ static void filemap_unaccount_folio(struct address_space *mapping,
VM_BUG_ON_FOLIO(folio_mapped(folio), folio);
if (!IS_ENABLED(CONFIG_DEBUG_VM) && unlikely(folio_mapped(folio))) {
pr_alert("BUG: Bad page cache in process %s pfn:%05lx\n",
- current->comm, folio_pfn(folio));
+ current->comm_str, folio_pfn(folio));
dump_page(&folio->page, "still mapped when deleted");
dump_stack();
add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
@@ -4084,7 +4084,7 @@ static void dio_warn_stale_pagecache(struct file *filp)
path = "(unknown)";
pr_crit("Page cache invalidation failure on direct I/O. Possible data corruption due to collision with buffered I/O!\n");
pr_crit("File: %s PID: %d Comm: %.20s\n", path, current->pid,
- current->comm);
+ current->comm_str);
}
}
diff --git a/mm/gup.c b/mm/gup.c
index adffe663594d..ca529d439e72 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1308,7 +1308,7 @@ static struct vm_area_struct *gup_vma_lookup(struct mm_struct *mm,
/* Let people know things may have changed. */
pr_warn("GUP no longer grows the stack in %s (%d): %lx-%lx (%lx)\n",
- current->comm, task_pid_nr(current),
+ current->comm_str, task_pid_nr(current),
vma->vm_start, vma->vm_end, addr);
dump_stack();
return NULL;
diff --git a/mm/memfd.c b/mm/memfd.c
index bbe679895ef6..acfdb41ed161 100644
--- a/mm/memfd.c
+++ b/mm/memfd.c
@@ -331,7 +331,7 @@ static int check_sysctl_memfd_noexec(unsigned int *flags)
if (!(*flags & MFD_NOEXEC_SEAL) && sysctl >= MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED) {
pr_err_ratelimited(
"%s[%d]: memfd_create() requires MFD_NOEXEC_SEAL with vm.memfd_noexec=%d\n",
- current->comm, task_pid_nr(current), sysctl);
+ current->comm_str, task_pid_nr(current), sysctl);
return -EACCES;
}
#endif
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 003b51e4adc0..b81dd0b7a5a3 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -354,7 +354,7 @@ static int kill_proc(struct to_kill *tk, unsigned long pfn, int flags)
int ret = 0;
pr_err("%#lx: Sending SIGBUS to %s:%d due to hardware memory corruption\n",
- pfn, t->comm, task_pid_nr(t));
+ pfn, t->comm_str, task_pid_nr(t));
if ((flags & MF_ACTION_REQUIRED) && (t == current))
ret = force_sig_mceerr(BUS_MCEERR_AR,
@@ -370,7 +370,7 @@ static int kill_proc(struct to_kill *tk, unsigned long pfn, int flags)
addr_lsb, t);
if (ret < 0)
pr_info("Error sending signal to %s:%d: %d\n",
- t->comm, task_pid_nr(t), ret);
+ t->comm_str, task_pid_nr(t), ret);
return ret;
}
@@ -475,7 +475,7 @@ static void __add_to_kill(struct task_struct *tsk, const struct page *p,
*/
if (tk->addr == -EFAULT) {
pr_info("Unable to find user space address %lx in %s\n",
- page_to_pfn(p), tsk->comm);
+ page_to_pfn(p), tsk->comm_str);
} else if (tk->size_shift == 0) {
kfree(tk);
return;
@@ -532,7 +532,7 @@ static void kill_procs(struct list_head *to_kill, int forcekill,
if (forcekill) {
if (tk->addr == -EFAULT) {
pr_err("%#lx: forcibly killing %s:%d because of failure to unmap corrupted page\n",
- pfn, tk->tsk->comm, task_pid_nr(tk->tsk));
+ pfn, tk->tsk->comm_str, task_pid_nr(tk->tsk));
do_send_sig_info(SIGKILL, SEND_SIG_PRIV,
tk->tsk, PIDTYPE_PID);
}
@@ -545,7 +545,7 @@ static void kill_procs(struct list_head *to_kill, int forcekill,
*/
else if (kill_proc(tk, pfn, flags) < 0)
pr_err("%#lx: Cannot send advisory machine check signal to %s:%d\n",
- pfn, tk->tsk->comm, task_pid_nr(tk->tsk));
+ pfn, tk->tsk->comm_str, task_pid_nr(tk->tsk));
}
list_del(&tk->nd);
put_task_struct(tk->tsk);
diff --git a/mm/memory.c b/mm/memory.c
index 4020639593ce..c7049ced1ae3 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -540,7 +540,7 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr,
index = linear_page_index(vma, addr);
pr_alert("BUG: Bad page map in process %s pte:%08llx pmd:%08llx\n",
- current->comm,
+ current->comm_str,
(long long)pte_val(pte), (long long)pmd_val(*pmd));
if (page)
dump_page(page, "bad pte");
diff --git a/mm/mmap.c b/mm/mmap.c
index 7306253cc3b5..c5971b26b005 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1096,7 +1096,7 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
vm_flags_t vm_flags;
pr_warn_once("%s (%d) uses deprecated remap_file_pages() syscall. See Documentation/mm/remap_file_pages.rst.\n",
- current->comm, current->pid);
+ current->comm_str, current->pid);
if (prot)
return ret;
@@ -1334,7 +1334,7 @@ bool may_expand_vm(struct mm_struct *mm, vm_flags_t flags, unsigned long npages)
return true;
pr_warn_once("%s (%d): VmData %lu exceed data ulimit %lu. Update limits%s.\n",
- current->comm, current->pid,
+ current->comm_str, current->pid,
(mm->data_vm + npages) << PAGE_SHIFT,
rlimit(RLIMIT_DATA),
ignore_rlimit_data ? "" : " or use boot option ignore_rlimit_data");
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index 25923cfec9c6..023eec5ec9c3 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -406,7 +406,7 @@ static int dump_task(struct task_struct *p, void *arg)
get_mm_counter(task->mm, MM_ANONPAGES), get_mm_counter(task->mm, MM_FILEPAGES),
get_mm_counter(task->mm, MM_SHMEMPAGES), mm_pgtables_bytes(task->mm),
get_mm_counter(task->mm, MM_SWAPENTS),
- task->signal->oom_score_adj, task->comm);
+ task->signal->oom_score_adj, task->comm_str);
task_unlock(task);
return 0;
@@ -452,14 +452,14 @@ static void dump_oom_victim(struct oom_control *oc, struct task_struct *victim)
nodemask_pr_args(oc->nodemask));
cpuset_print_current_mems_allowed();
mem_cgroup_print_oom_context(oc->memcg, victim);
- pr_cont(",task=%s,pid=%d,uid=%d\n", victim->comm, victim->pid,
+ pr_cont(",task=%s,pid=%d,uid=%d\n", victim->comm_str, victim->pid,
from_kuid(&init_user_ns, task_uid(victim)));
}
static void dump_header(struct oom_control *oc)
{
pr_warn("%s invoked oom-killer: gfp_mask=%#x(%pGg), order=%d, oom_score_adj=%hd\n",
- current->comm, oc->gfp_mask, &oc->gfp_mask, oc->order,
+ current->comm_str, oc->gfp_mask, &oc->gfp_mask, oc->order,
current->signal->oom_score_adj);
if (!IS_ENABLED(CONFIG_COMPACTION) && oc->order)
pr_warn("COMPACTION is disabled!!!\n");
@@ -596,7 +596,7 @@ static bool oom_reap_task_mm(struct task_struct *tsk, struct mm_struct *mm)
goto out_finish;
pr_info("oom_reaper: reaped process %d (%s), now anon-rss:%lukB, file-rss:%lukB, shmem-rss:%lukB\n",
- task_pid_nr(tsk), tsk->comm,
+ task_pid_nr(tsk), tsk->comm_str,
K(get_mm_counter(mm, MM_ANONPAGES)),
K(get_mm_counter(mm, MM_FILEPAGES)),
K(get_mm_counter(mm, MM_SHMEMPAGES)));
@@ -623,7 +623,7 @@ static void oom_reap_task(struct task_struct *tsk)
goto done;
pr_info("oom_reaper: unable to reap pid:%d (%s)\n",
- task_pid_nr(tsk), tsk->comm);
+ task_pid_nr(tsk), tsk->comm_str);
sched_show_task(tsk);
debug_show_all_locks();
@@ -927,7 +927,7 @@ static void __oom_kill_process(struct task_struct *victim, const char *message)
p = find_lock_task_mm(victim);
if (!p) {
pr_info("%s: OOM victim %d (%s) is already exiting. Skip killing the task\n",
- message, task_pid_nr(victim), victim->comm);
+ message, task_pid_nr(victim), victim->comm_str);
put_task_struct(victim);
return;
} else if (victim != p) {
@@ -952,7 +952,7 @@ static void __oom_kill_process(struct task_struct *victim, const char *message)
do_send_sig_info(SIGKILL, SEND_SIG_PRIV, victim, PIDTYPE_TGID);
mark_oom_victim(victim);
pr_err("%s: Killed process %d (%s) total-vm:%lukB, anon-rss:%lukB, file-rss:%lukB, shmem-rss:%lukB, UID:%u pgtables:%lukB oom_score_adj:%hd\n",
- message, task_pid_nr(victim), victim->comm, K(mm->total_vm),
+ message, task_pid_nr(victim), victim->comm_str, K(mm->total_vm),
K(get_mm_counter(mm, MM_ANONPAGES)),
K(get_mm_counter(mm, MM_FILEPAGES)),
K(get_mm_counter(mm, MM_SHMEMPAGES)),
@@ -979,8 +979,8 @@ static void __oom_kill_process(struct task_struct *victim, const char *message)
can_oom_reap = false;
set_bit(MMF_OOM_SKIP, &mm->flags);
pr_info("oom killer %d (%s) has mm pinned by %d (%s)\n",
- task_pid_nr(victim), victim->comm,
- task_pid_nr(p), p->comm);
+ task_pid_nr(victim), victim->comm_str,
+ task_pid_nr(p), p->comm_str);
continue;
}
/*
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index fa09154a799c..92de19bdf9d4 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -643,7 +643,7 @@ static void bad_page(struct page *page, const char *reason)
resume = jiffies + 60 * HZ;
pr_alert("BUG: Bad page state in process %s pfn:%05lx\n",
- current->comm, page_to_pfn(page));
+ current->comm_str, page_to_pfn(page));
dump_page(page, reason);
print_modules();
@@ -3923,7 +3923,7 @@ void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...)
vaf.fmt = fmt;
vaf.va = &args;
pr_warn("%s: %pV, mode:%#x(%pGg), nodemask=%*pbl",
- current->comm, &vaf, gfp_mask, &gfp_mask,
+ current->comm_str, &vaf, gfp_mask, &gfp_mask,
nodemask_pr_args(nodemask));
va_end(args);
diff --git a/mm/util.c b/mm/util.c
index 68ea833ba25f..0995f8e90edb 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -965,7 +965,7 @@ int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin)
error:
bytes_failed = pages << PAGE_SHIFT;
pr_warn_ratelimited("%s: pid: %d, comm: %s, bytes: %lu not enough memory for the allocation\n",
- __func__, current->pid, current->comm, bytes_failed);
+ __func__, current->pid, current->comm_str, bytes_failed);
vm_unacct_memory(pages);
return -ENOMEM;
diff --git a/net/core/sock.c b/net/core/sock.c
index 8b7623c7d547..516eab62f3c9 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -443,7 +443,7 @@ static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
if (warned < 10 && net_ratelimit()) {
warned++;
pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
- __func__, current->comm, task_pid_nr(current));
+ __func__, current->comm_str, task_pid_nr(current));
}
return 0;
}
diff --git a/net/dns_resolver/internal.h b/net/dns_resolver/internal.h
index 0c570d40e4d6..447b1256bf42 100644
--- a/net/dns_resolver/internal.h
+++ b/net/dns_resolver/internal.h
@@ -44,7 +44,7 @@ extern unsigned int dns_resolver_debug;
do { \
if (unlikely(dns_resolver_debug)) \
printk(KERN_DEBUG "[%-6.6s] "FMT"\n", \
- current->comm, ##__VA_ARGS__); \
+ current->comm_str, ##__VA_ARGS__); \
} while (0)
#define kenter(FMT, ...) kdebug("==> %s("FMT")", __func__, ##__VA_ARGS__)
diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index 1d2c89d63cc7..5037968c95dd 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -520,7 +520,7 @@ static int raw_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
goto out;
if (usin->sin_family != AF_INET) {
pr_info_once("%s: %s forgot to set AF_INET. Fix it!\n",
- __func__, current->comm);
+ __func__, current->comm_str);
err = -EAFNOSUPPORT;
if (usin->sin_family)
goto out;
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 31149a0ac849..c98e4d577ea3 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2761,7 +2761,7 @@ static int tcp_recvmsg_locked(struct sock *sk, struct msghdr *msg, size_t len,
if ((flags & MSG_PEEK) &&
(peek_seq - peek_offset - copied - urg_hole != tp->copied_seq)) {
net_dbg_ratelimited("TCP(%s:%d): Application bug, race in MSG_PEEK\n",
- current->comm,
+ current->comm_str,
task_pid_nr(current));
peek_seq = tp->copied_seq + peek_offset;
}
diff --git a/net/socket.c b/net/socket.c
index 682969deaed3..df2f3d0c10b4 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -1537,7 +1537,7 @@ int __sock_create(struct net *net, int family, int type, int protocol,
*/
if (family == PF_INET && type == SOCK_PACKET) {
pr_info_once("%s uses obsolete (PF_INET,SOCK_PACKET)\n",
- current->comm);
+ current->comm_str);
family = PF_PACKET;
}
diff --git a/security/lsm_audit.c b/security/lsm_audit.c
index 7d623b00495c..c64dce81e4f2 100644
--- a/security/lsm_audit.c
+++ b/security/lsm_audit.c
@@ -274,7 +274,7 @@ void audit_log_lsm_data(struct audit_buffer *ab,
if (tsk) {
pid_t pid = task_tgid_nr(tsk);
if (pid) {
- char tskcomm[sizeof(tsk->comm)];
+ char tskcomm[TASK_COMM_LEN];
audit_log_format(ab, " opid=%d ocomm=", pid);
audit_log_untrustedstring(ab,
get_task_comm(tskcomm, tsk));
@@ -414,7 +414,7 @@ void audit_log_lsm_data(struct audit_buffer *ab,
static void dump_common_audit_data(struct audit_buffer *ab,
const struct common_audit_data *a)
{
- char comm[sizeof(current->comm)];
+ char comm[TASK_COMM_LEN];
audit_log_format(ab, " pid=%d comm=", task_tgid_nr(current));
audit_log_untrustedstring(ab, get_task_comm(comm, current));
--
2.38.1
^ permalink raw reply related [flat|nested] 12+ messages in thread
* Re: [PATCH v5 3/3] treewide: Switch from tsk->comm to tsk->comm_str which is 64 bytes long
2025-07-16 12:39 ` [PATCH v5 3/3] treewide: Switch from tsk->comm to tsk->comm_str which is 64 bytes long Bhupesh
@ 2025-07-16 18:10 ` Andrii Nakryiko
2025-07-16 20:18 ` Bhupesh Sharma
2025-07-17 4:23 ` kernel test robot
2025-07-24 9:16 ` Askar Safin
2 siblings, 1 reply; 12+ messages in thread
From: Andrii Nakryiko @ 2025-07-16 18:10 UTC (permalink / raw)
To: Bhupesh
Cc: akpm, kernel-dev, linux-kernel, bpf, linux-perf-users,
linux-fsdevel, linux-mm, oliver.sang, lkp, laoar.shao, pmladek,
rostedt, mathieu.desnoyers, arnaldo.melo, alexei.starovoitov,
mirq-linux, peterz, willy, david, viro, keescook, ebiederm,
brauner, jack, mingo, juri.lelli, bsegall, mgorman, vschneid,
linux-trace-kernel, kees, torvalds
On Wed, Jul 16, 2025 at 5:40 AM Bhupesh <bhupesh@igalia.com> wrote:
>
> Historically due to the 16-byte length of TASK_COMM_LEN, the
> users of 'tsk->comm' are restricted to use a fixed-size target
> buffer also of TASK_COMM_LEN for 'memcpy()' like use-cases.
>
> To fix the same, Kees suggested in [1] that we can replace tsk->comm,
> with tsk->comm_str, inside 'task_struct':
> union {
> char comm_str[TASK_COMM_EXT_LEN];
> };
>
> where TASK_COMM_EXT_LEN is 64-bytes.
Do we absolutely have to rename task->comm field? I understand as an
intermediate step to not miss any existing users in the kernel
sources, but once that all is done, we can rename that back to comm,
right?
The reason I'm asking is because accessing task->comm is *very common*
with all sorts of BPF programs and scripts. Yes, we have way to deal
with that with BPF CO-RE, but every single use case would need to be
updated now to work both with task->comm name on old kernels and
task->comm_str on new kernels (because BPF programs are written in
more or less kernel version agnostic way, so they have to handle many
kernel releases).
So, unless absolutely necessary, can we please keep the field name the
same? Changing the size of that field is not really a problem for BPF,
so no objections against that.
>
> And then modify 'get_task_comm()' to pass 'tsk->comm_str'
> to the existing users.
>
> This would mean that ABI is maintained while ensuring that:
>
> - Existing users of 'get_task_comm'/ 'set_task_comm' will get 'tsk->comm_str'
> truncated to a maximum of 'TASK_COMM_LEN' (16-bytes) to maintain ABI,
> - New / Modified users of 'get_task_comm'/ 'set_task_comm' will get
> 'tsk->comm_str' supported for a maximum of 'TASK_COMM_EXTLEN' (64-bytes).
>
> Note, that the existing users have not been modified to migrate to
> 'TASK_COMM_EXT_LEN', in case they have hard-coded expectations of
> dealing with only a 'TASK_COMM_LEN' long 'tsk->comm_str'.
>
> [1]. https://lore.kernel.org/all/202505231346.52F291C54@keescook/
>
> Signed-off-by: Bhupesh <bhupesh@igalia.com>
> ---
> arch/arm64/kernel/traps.c | 2 +-
> arch/arm64/kvm/mmu.c | 2 +-
> block/blk-core.c | 2 +-
> block/bsg.c | 2 +-
> drivers/char/random.c | 2 +-
> drivers/hid/hid-core.c | 6 +++---
> drivers/mmc/host/tmio_mmc_core.c | 6 +++---
> drivers/pci/pci-sysfs.c | 2 +-
> drivers/scsi/scsi_ioctl.c | 2 +-
> drivers/tty/serial/serial_core.c | 2 +-
> drivers/tty/tty_io.c | 8 ++++----
> drivers/usb/core/devio.c | 16 ++++++++--------
> drivers/usb/core/message.c | 2 +-
> drivers/vfio/group.c | 2 +-
> drivers/vfio/vfio_iommu_type1.c | 2 +-
> drivers/vfio/vfio_main.c | 2 +-
> drivers/xen/evtchn.c | 2 +-
> drivers/xen/grant-table.c | 2 +-
> fs/binfmt_elf.c | 2 +-
> fs/coredump.c | 4 ++--
> fs/drop_caches.c | 2 +-
> fs/exec.c | 8 ++++----
> fs/ext4/dir.c | 2 +-
> fs/ext4/inode.c | 2 +-
> fs/ext4/namei.c | 2 +-
> fs/ext4/super.c | 12 ++++++------
> fs/hugetlbfs/inode.c | 2 +-
> fs/ioctl.c | 2 +-
> fs/iomap/direct-io.c | 2 +-
> fs/jbd2/transaction.c | 2 +-
> fs/locks.c | 2 +-
> fs/netfs/internal.h | 2 +-
> fs/proc/base.c | 2 +-
> fs/read_write.c | 2 +-
> fs/splice.c | 2 +-
> include/linux/coredump.h | 2 +-
> include/linux/filter.h | 2 +-
> include/linux/ratelimit.h | 2 +-
> include/linux/sched.h | 11 ++++++++---
> init/init_task.c | 2 +-
> ipc/sem.c | 2 +-
> kernel/acct.c | 2 +-
> kernel/audit.c | 4 ++--
> kernel/auditsc.c | 10 +++++-----
> kernel/bpf/helpers.c | 2 +-
> kernel/capability.c | 4 ++--
> kernel/cgroup/cgroup-v1.c | 2 +-
> kernel/cred.c | 4 ++--
> kernel/events/core.c | 2 +-
> kernel/exit.c | 6 +++---
> kernel/fork.c | 9 +++++++--
> kernel/freezer.c | 4 ++--
> kernel/futex/waitwake.c | 2 +-
> kernel/hung_task.c | 10 +++++-----
> kernel/irq/manage.c | 2 +-
> kernel/kthread.c | 2 +-
> kernel/locking/rtmutex.c | 2 +-
> kernel/printk/printk.c | 2 +-
> kernel/sched/core.c | 22 +++++++++++-----------
> kernel/sched/debug.c | 4 ++--
> kernel/signal.c | 6 +++---
> kernel/sys.c | 6 +++---
> kernel/sysctl.c | 2 +-
> kernel/time/itimer.c | 4 ++--
> kernel/time/posix-cpu-timers.c | 2 +-
> kernel/tsacct.c | 2 +-
> kernel/workqueue.c | 6 +++---
> lib/dump_stack.c | 2 +-
> lib/nlattr.c | 6 +++---
> mm/compaction.c | 2 +-
> mm/filemap.c | 4 ++--
> mm/gup.c | 2 +-
> mm/memfd.c | 2 +-
> mm/memory-failure.c | 10 +++++-----
> mm/memory.c | 2 +-
> mm/mmap.c | 4 ++--
> mm/oom_kill.c | 18 +++++++++---------
> mm/page_alloc.c | 4 ++--
> mm/util.c | 2 +-
> net/core/sock.c | 2 +-
> net/dns_resolver/internal.h | 2 +-
> net/ipv4/raw.c | 2 +-
> net/ipv4/tcp.c | 2 +-
> net/socket.c | 2 +-
> security/lsm_audit.c | 4 ++--
> 85 files changed, 171 insertions(+), 161 deletions(-)
>
[...]
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH v5 3/3] treewide: Switch from tsk->comm to tsk->comm_str which is 64 bytes long
2025-07-16 18:10 ` Andrii Nakryiko
@ 2025-07-16 20:18 ` Bhupesh Sharma
2025-07-16 20:47 ` Andrii Nakryiko
0 siblings, 1 reply; 12+ messages in thread
From: Bhupesh Sharma @ 2025-07-16 20:18 UTC (permalink / raw)
To: Andrii Nakryiko, Bhupesh
Cc: akpm, kernel-dev, linux-kernel, bpf, linux-perf-users,
linux-fsdevel, linux-mm, oliver.sang, lkp, laoar.shao, pmladek,
rostedt, mathieu.desnoyers, arnaldo.melo, alexei.starovoitov,
mirq-linux, peterz, willy, david, viro, keescook, ebiederm,
brauner, jack, mingo, juri.lelli, bsegall, mgorman, vschneid,
linux-trace-kernel, kees, torvalds
On 7/16/25 11:40 PM, Andrii Nakryiko wrote:
> On Wed, Jul 16, 2025 at 5:40 AM Bhupesh <bhupesh@igalia.com> wrote:
>> Historically due to the 16-byte length of TASK_COMM_LEN, the
>> users of 'tsk->comm' are restricted to use a fixed-size target
>> buffer also of TASK_COMM_LEN for 'memcpy()' like use-cases.
>>
>> To fix the same, Kees suggested in [1] that we can replace tsk->comm,
>> with tsk->comm_str, inside 'task_struct':
>> union {
>> char comm_str[TASK_COMM_EXT_LEN];
>> };
>>
>> where TASK_COMM_EXT_LEN is 64-bytes.
> Do we absolutely have to rename task->comm field? I understand as an
> intermediate step to not miss any existing users in the kernel
> sources, but once that all is done, we can rename that back to comm,
> right?
>
> The reason I'm asking is because accessing task->comm is *very common*
> with all sorts of BPF programs and scripts. Yes, we have way to deal
> with that with BPF CO-RE, but every single use case would need to be
> updated now to work both with task->comm name on old kernels and
> task->comm_str on new kernels (because BPF programs are written in
> more or less kernel version agnostic way, so they have to handle many
> kernel releases).
>
> So, unless absolutely necessary, can we please keep the field name the
> same? Changing the size of that field is not really a problem for BPF,
> so no objections against that.
So, as a background we have had several previous discussions regarding
renaming the 'tsk->comm' to 'task->comm_str' on the list (please see [1]
and [2] for details), and as per Kees's recommendations we have taken
this approach in the v5 patchset (may be Kees can add further details if
I have missed adding something in the log message above).
That being said, ideally one would not like to break any exiting ABI
(which includes existing / older BPF programs). I was having a look at
the BPF CO_RE reference guide (see [3]), and was able to make out that
BPF CO_RE has a definition of |s||truct task_struct|which doesn't need
to match the kernel's struct task_struct definition exactly (as [3]
mentions -> only a necessary subset of fields have to be present and
compatible):
|struct task_struct { intpid; charcomm[16]; struct
task_struct*group_leader; } __attribute__((preserve_access_index)); |
So, if we add a check here to add '|charcomm[16]' or||charcomm_str[16]'
to BPF CO RE's internal 'struct task_struct' on basis of the underlying
kernel version being used (something like using 'KERNEL_VERSION(x, y,
0)' for example), will that suffice? I have ||used and seen these checks
being used in the user-space applications (for example, see [4]) at
several occasions.
Please let me know your views.
|[1]. https://lore.kernel.org/all/202505222041.B639D482FB@keescook/
[2].
https://lore.kernel.org/all/ba4ddf27-91e7-0ecc-95d5-c139f6978812@igalia.com/
[3]. https://nakryiko.com/posts/bpf-core-reference-guide/
[4].
https://github.com/crash-utility/crash/blob/master/memory_driver/crash.c#L41C25-L41C49
Thanks.
>> And then modify 'get_task_comm()' to pass 'tsk->comm_str'
>> to the existing users.
>>
>> This would mean that ABI is maintained while ensuring that:
>>
>> - Existing users of 'get_task_comm'/ 'set_task_comm' will get 'tsk->comm_str'
>> truncated to a maximum of 'TASK_COMM_LEN' (16-bytes) to maintain ABI,
>> - New / Modified users of 'get_task_comm'/ 'set_task_comm' will get
>> 'tsk->comm_str' supported for a maximum of 'TASK_COMM_EXTLEN' (64-bytes).
>>
>> Note, that the existing users have not been modified to migrate to
>> 'TASK_COMM_EXT_LEN', in case they have hard-coded expectations of
>> dealing with only a 'TASK_COMM_LEN' long 'tsk->comm_str'.
>>
>> [1]. https://lore.kernel.org/all/202505231346.52F291C54@keescook/
>>
>> Signed-off-by: Bhupesh <bhupesh@igalia.com>
>> ---
>> arch/arm64/kernel/traps.c | 2 +-
>> arch/arm64/kvm/mmu.c | 2 +-
>> block/blk-core.c | 2 +-
>> block/bsg.c | 2 +-
>> drivers/char/random.c | 2 +-
>> drivers/hid/hid-core.c | 6 +++---
>> drivers/mmc/host/tmio_mmc_core.c | 6 +++---
>> drivers/pci/pci-sysfs.c | 2 +-
>> drivers/scsi/scsi_ioctl.c | 2 +-
>> drivers/tty/serial/serial_core.c | 2 +-
>> drivers/tty/tty_io.c | 8 ++++----
>> drivers/usb/core/devio.c | 16 ++++++++--------
>> drivers/usb/core/message.c | 2 +-
>> drivers/vfio/group.c | 2 +-
>> drivers/vfio/vfio_iommu_type1.c | 2 +-
>> drivers/vfio/vfio_main.c | 2 +-
>> drivers/xen/evtchn.c | 2 +-
>> drivers/xen/grant-table.c | 2 +-
>> fs/binfmt_elf.c | 2 +-
>> fs/coredump.c | 4 ++--
>> fs/drop_caches.c | 2 +-
>> fs/exec.c | 8 ++++----
>> fs/ext4/dir.c | 2 +-
>> fs/ext4/inode.c | 2 +-
>> fs/ext4/namei.c | 2 +-
>> fs/ext4/super.c | 12 ++++++------
>> fs/hugetlbfs/inode.c | 2 +-
>> fs/ioctl.c | 2 +-
>> fs/iomap/direct-io.c | 2 +-
>> fs/jbd2/transaction.c | 2 +-
>> fs/locks.c | 2 +-
>> fs/netfs/internal.h | 2 +-
>> fs/proc/base.c | 2 +-
>> fs/read_write.c | 2 +-
>> fs/splice.c | 2 +-
>> include/linux/coredump.h | 2 +-
>> include/linux/filter.h | 2 +-
>> include/linux/ratelimit.h | 2 +-
>> include/linux/sched.h | 11 ++++++++---
>> init/init_task.c | 2 +-
>> ipc/sem.c | 2 +-
>> kernel/acct.c | 2 +-
>> kernel/audit.c | 4 ++--
>> kernel/auditsc.c | 10 +++++-----
>> kernel/bpf/helpers.c | 2 +-
>> kernel/capability.c | 4 ++--
>> kernel/cgroup/cgroup-v1.c | 2 +-
>> kernel/cred.c | 4 ++--
>> kernel/events/core.c | 2 +-
>> kernel/exit.c | 6 +++---
>> kernel/fork.c | 9 +++++++--
>> kernel/freezer.c | 4 ++--
>> kernel/futex/waitwake.c | 2 +-
>> kernel/hung_task.c | 10 +++++-----
>> kernel/irq/manage.c | 2 +-
>> kernel/kthread.c | 2 +-
>> kernel/locking/rtmutex.c | 2 +-
>> kernel/printk/printk.c | 2 +-
>> kernel/sched/core.c | 22 +++++++++++-----------
>> kernel/sched/debug.c | 4 ++--
>> kernel/signal.c | 6 +++---
>> kernel/sys.c | 6 +++---
>> kernel/sysctl.c | 2 +-
>> kernel/time/itimer.c | 4 ++--
>> kernel/time/posix-cpu-timers.c | 2 +-
>> kernel/tsacct.c | 2 +-
>> kernel/workqueue.c | 6 +++---
>> lib/dump_stack.c | 2 +-
>> lib/nlattr.c | 6 +++---
>> mm/compaction.c | 2 +-
>> mm/filemap.c | 4 ++--
>> mm/gup.c | 2 +-
>> mm/memfd.c | 2 +-
>> mm/memory-failure.c | 10 +++++-----
>> mm/memory.c | 2 +-
>> mm/mmap.c | 4 ++--
>> mm/oom_kill.c | 18 +++++++++---------
>> mm/page_alloc.c | 4 ++--
>> mm/util.c | 2 +-
>> net/core/sock.c | 2 +-
>> net/dns_resolver/internal.h | 2 +-
>> net/ipv4/raw.c | 2 +-
>> net/ipv4/tcp.c | 2 +-
>> net/socket.c | 2 +-
>> security/lsm_audit.c | 4 ++--
>> 85 files changed, 171 insertions(+), 161 deletions(-)
>>
> [...]
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH v5 3/3] treewide: Switch from tsk->comm to tsk->comm_str which is 64 bytes long
2025-07-16 20:18 ` Bhupesh Sharma
@ 2025-07-16 20:47 ` Andrii Nakryiko
2025-07-17 18:35 ` Linus Torvalds
0 siblings, 1 reply; 12+ messages in thread
From: Andrii Nakryiko @ 2025-07-16 20:47 UTC (permalink / raw)
To: Bhupesh Sharma
Cc: Bhupesh, akpm, kernel-dev, linux-kernel, bpf, linux-perf-users,
linux-fsdevel, linux-mm, oliver.sang, lkp, laoar.shao, pmladek,
rostedt, mathieu.desnoyers, arnaldo.melo, alexei.starovoitov,
mirq-linux, peterz, willy, david, viro, keescook, ebiederm,
brauner, jack, mingo, juri.lelli, bsegall, mgorman, vschneid,
linux-trace-kernel, kees, torvalds
On Wed, Jul 16, 2025 at 1:18 PM Bhupesh Sharma <bhsharma@igalia.com> wrote:
>
> On 7/16/25 11:40 PM, Andrii Nakryiko wrote:
> > On Wed, Jul 16, 2025 at 5:40 AM Bhupesh <bhupesh@igalia.com> wrote:
> >> Historically due to the 16-byte length of TASK_COMM_LEN, the
> >> users of 'tsk->comm' are restricted to use a fixed-size target
> >> buffer also of TASK_COMM_LEN for 'memcpy()' like use-cases.
> >>
> >> To fix the same, Kees suggested in [1] that we can replace tsk->comm,
> >> with tsk->comm_str, inside 'task_struct':
> >> union {
> >> char comm_str[TASK_COMM_EXT_LEN];
> >> };
> >>
> >> where TASK_COMM_EXT_LEN is 64-bytes.
> > Do we absolutely have to rename task->comm field? I understand as an
> > intermediate step to not miss any existing users in the kernel
> > sources, but once that all is done, we can rename that back to comm,
> > right?
> >
> > The reason I'm asking is because accessing task->comm is *very common*
> > with all sorts of BPF programs and scripts. Yes, we have way to deal
> > with that with BPF CO-RE, but every single use case would need to be
> > updated now to work both with task->comm name on old kernels and
> > task->comm_str on new kernels (because BPF programs are written in
> > more or less kernel version agnostic way, so they have to handle many
> > kernel releases).
> >
> > So, unless absolutely necessary, can we please keep the field name the
> > same? Changing the size of that field is not really a problem for BPF,
> > so no objections against that.
>
> So, as a background we have had several previous discussions regarding
> renaming the 'tsk->comm' to 'task->comm_str' on the list (please see [1]
> and [2] for details), and as per Kees's recommendations we have taken
> this approach in the v5 patchset (may be Kees can add further details if
> I have missed adding something in the log message above).
>
> That being said, ideally one would not like to break any exiting ABI
kernel-internal data structures are not ABI to BPF programs, even
though they do look into kernel internals routinely for observability
and other reasons, so there is no ABI/API stability issue here.
Having said that, unless absolutely necessary, renaming something so
commonly used as task->comm is just an unnecessary widespread
disruption, which ideally we just avoid, unless absolutely necessary.
> (which includes existing / older BPF programs). I was having a look at
> the BPF CO_RE reference guide (see [3]), and was able to make out that
> BPF CO_RE has a definition of |s||truct task_struct|which doesn't need
> to match the kernel's struct task_struct definition exactly (as [3]
> mentions -> only a necessary subset of fields have to be present and
> compatible):
>
> |struct task_struct { intpid; charcomm[16]; struct
> task_struct*group_leader; } __attribute__((preserve_access_index)); |
>
> So, if we add a check here to add '|charcomm[16]' or||charcomm_str[16]'
> to BPF CO RE's internal 'struct task_struct' on basis of the underlying
> kernel version being used (something like using 'KERNEL_VERSION(x, y,
> 0)' for example), will that suffice? I have ||used and seen these checks
> being used in the user-space applications (for example, see [4]) at
> several occasions.
>
It's simpler on BPF side, we can check the existence of task_struct's
comm field, and handle either task->comm or task->comm_str
accordingly. This has been done many times for various things that
evolved in the kernel.
But given how frequently task->comm is referenced (pretty much any
profiler or tracer will capture this), it's just the widespread nature
of accessing task->comm in BPF programs/scripts that will cause a lot
of adaptation churn. And given the reason for renaming was to catch
missing cases during refactoring, my ask was to do this renaming
locally, validate all kernel code was modified, and then switch the
field name back to "comm" (which you already did, so the remaining
part would be just to rename comm_str back to comm). Unless I'm
missing something else, of course.
> Please let me know your views.
>
> |[1]. https://lore.kernel.org/all/202505222041.B639D482FB@keescook/
> [2].
> https://lore.kernel.org/all/ba4ddf27-91e7-0ecc-95d5-c139f6978812@igalia.com/
> [3]. https://nakryiko.com/posts/bpf-core-reference-guide/
> [4].
> https://github.com/crash-utility/crash/blob/master/memory_driver/crash.c#L41C25-L41C49
>
> Thanks.
>
> >> And then modify 'get_task_comm()' to pass 'tsk->comm_str'
> >> to the existing users.
> >>
> >> This would mean that ABI is maintained while ensuring that:
> >>
> >> - Existing users of 'get_task_comm'/ 'set_task_comm' will get 'tsk->comm_str'
> >> truncated to a maximum of 'TASK_COMM_LEN' (16-bytes) to maintain ABI,
> >> - New / Modified users of 'get_task_comm'/ 'set_task_comm' will get
> >> 'tsk->comm_str' supported for a maximum of 'TASK_COMM_EXTLEN' (64-bytes).
> >>
> >> Note, that the existing users have not been modified to migrate to
> >> 'TASK_COMM_EXT_LEN', in case they have hard-coded expectations of
> >> dealing with only a 'TASK_COMM_LEN' long 'tsk->comm_str'.
> >>
> >> [1]. https://lore.kernel.org/all/202505231346.52F291C54@keescook/
> >>
> >> Signed-off-by: Bhupesh <bhupesh@igalia.com>
> >> ---
> >> arch/arm64/kernel/traps.c | 2 +-
> >> arch/arm64/kvm/mmu.c | 2 +-
> >> block/blk-core.c | 2 +-
> >> block/bsg.c | 2 +-
> >> drivers/char/random.c | 2 +-
> >> drivers/hid/hid-core.c | 6 +++---
> >> drivers/mmc/host/tmio_mmc_core.c | 6 +++---
> >> drivers/pci/pci-sysfs.c | 2 +-
> >> drivers/scsi/scsi_ioctl.c | 2 +-
> >> drivers/tty/serial/serial_core.c | 2 +-
> >> drivers/tty/tty_io.c | 8 ++++----
> >> drivers/usb/core/devio.c | 16 ++++++++--------
> >> drivers/usb/core/message.c | 2 +-
> >> drivers/vfio/group.c | 2 +-
> >> drivers/vfio/vfio_iommu_type1.c | 2 +-
> >> drivers/vfio/vfio_main.c | 2 +-
> >> drivers/xen/evtchn.c | 2 +-
> >> drivers/xen/grant-table.c | 2 +-
> >> fs/binfmt_elf.c | 2 +-
> >> fs/coredump.c | 4 ++--
> >> fs/drop_caches.c | 2 +-
> >> fs/exec.c | 8 ++++----
> >> fs/ext4/dir.c | 2 +-
> >> fs/ext4/inode.c | 2 +-
> >> fs/ext4/namei.c | 2 +-
> >> fs/ext4/super.c | 12 ++++++------
> >> fs/hugetlbfs/inode.c | 2 +-
> >> fs/ioctl.c | 2 +-
> >> fs/iomap/direct-io.c | 2 +-
> >> fs/jbd2/transaction.c | 2 +-
> >> fs/locks.c | 2 +-
> >> fs/netfs/internal.h | 2 +-
> >> fs/proc/base.c | 2 +-
> >> fs/read_write.c | 2 +-
> >> fs/splice.c | 2 +-
> >> include/linux/coredump.h | 2 +-
> >> include/linux/filter.h | 2 +-
> >> include/linux/ratelimit.h | 2 +-
> >> include/linux/sched.h | 11 ++++++++---
> >> init/init_task.c | 2 +-
> >> ipc/sem.c | 2 +-
> >> kernel/acct.c | 2 +-
> >> kernel/audit.c | 4 ++--
> >> kernel/auditsc.c | 10 +++++-----
> >> kernel/bpf/helpers.c | 2 +-
> >> kernel/capability.c | 4 ++--
> >> kernel/cgroup/cgroup-v1.c | 2 +-
> >> kernel/cred.c | 4 ++--
> >> kernel/events/core.c | 2 +-
> >> kernel/exit.c | 6 +++---
> >> kernel/fork.c | 9 +++++++--
> >> kernel/freezer.c | 4 ++--
> >> kernel/futex/waitwake.c | 2 +-
> >> kernel/hung_task.c | 10 +++++-----
> >> kernel/irq/manage.c | 2 +-
> >> kernel/kthread.c | 2 +-
> >> kernel/locking/rtmutex.c | 2 +-
> >> kernel/printk/printk.c | 2 +-
> >> kernel/sched/core.c | 22 +++++++++++-----------
> >> kernel/sched/debug.c | 4 ++--
> >> kernel/signal.c | 6 +++---
> >> kernel/sys.c | 6 +++---
> >> kernel/sysctl.c | 2 +-
> >> kernel/time/itimer.c | 4 ++--
> >> kernel/time/posix-cpu-timers.c | 2 +-
> >> kernel/tsacct.c | 2 +-
> >> kernel/workqueue.c | 6 +++---
> >> lib/dump_stack.c | 2 +-
> >> lib/nlattr.c | 6 +++---
> >> mm/compaction.c | 2 +-
> >> mm/filemap.c | 4 ++--
> >> mm/gup.c | 2 +-
> >> mm/memfd.c | 2 +-
> >> mm/memory-failure.c | 10 +++++-----
> >> mm/memory.c | 2 +-
> >> mm/mmap.c | 4 ++--
> >> mm/oom_kill.c | 18 +++++++++---------
> >> mm/page_alloc.c | 4 ++--
> >> mm/util.c | 2 +-
> >> net/core/sock.c | 2 +-
> >> net/dns_resolver/internal.h | 2 +-
> >> net/ipv4/raw.c | 2 +-
> >> net/ipv4/tcp.c | 2 +-
> >> net/socket.c | 2 +-
> >> security/lsm_audit.c | 4 ++--
> >> 85 files changed, 171 insertions(+), 161 deletions(-)
> >>
> > [...]
>
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH v5 3/3] treewide: Switch from tsk->comm to tsk->comm_str which is 64 bytes long
2025-07-16 12:39 ` [PATCH v5 3/3] treewide: Switch from tsk->comm to tsk->comm_str which is 64 bytes long Bhupesh
2025-07-16 18:10 ` Andrii Nakryiko
@ 2025-07-17 4:23 ` kernel test robot
2025-07-24 9:16 ` Askar Safin
2 siblings, 0 replies; 12+ messages in thread
From: kernel test robot @ 2025-07-17 4:23 UTC (permalink / raw)
To: Bhupesh, akpm
Cc: oe-kbuild-all, bhupesh, kernel-dev, linux-kernel, bpf,
linux-perf-users, linux-fsdevel, linux-mm, oliver.sang, lkp,
laoar.shao, pmladek, rostedt, mathieu.desnoyers, arnaldo.melo,
alexei.starovoitov, andrii.nakryiko, mirq-linux, peterz, willy,
david, viro, keescook, ebiederm, brauner, jack, mingo, juri.lelli,
bsegall, mgorman
Hi Bhupesh,
kernel test robot noticed the following build errors:
[auto build test ERROR on next-20250715]
[cannot apply to akpm-mm/mm-everything brauner-vfs/vfs.all tip/sched/core trace/for-next linus/master v6.16-rc6 v6.16-rc5 v6.16-rc4 v6.16-rc6]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Bhupesh/exec-Remove-obsolete-comments/20250716-204047
base: next-20250715
patch link: https://lore.kernel.org/r/20250716123916.511889-4-bhupesh%40igalia.com
patch subject: [PATCH v5 3/3] treewide: Switch from tsk->comm to tsk->comm_str which is 64 bytes long
config: i386-buildonly-randconfig-001-20250717 (https://download.01.org/0day-ci/archive/20250717/202507171254.FobDRyqP-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14+deb12u1) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250717/202507171254.FobDRyqP-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202507171254.FobDRyqP-lkp@intel.com/
All error/warnings (new ones prefixed by >>):
In file included from include/asm-generic/bug.h:28,
from arch/x86/include/asm/bug.h:103,
from arch/x86/include/asm/alternative.h:9,
from arch/x86/include/asm/atomic.h:7,
from include/linux/atomic.h:7,
from include/linux/debug_locks.h:5,
from kernel/panic.c:12:
kernel/panic.c: In function '__warn':
>> kernel/panic.c:818:58: error: 'struct task_struct' has no member named 'comm'; did you mean 'mm'?
818 | raw_smp_processor_id(), current->comm, current->pid);
| ^~~~
include/linux/printk.h:486:33: note: in definition of macro 'printk_index_wrap'
486 | _p_func(_fmt, ##__VA_ARGS__); \
| ^~~~~~~~~~~
include/linux/printk.h:567:9: note: in expansion of macro 'printk'
567 | printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
| ^~~~~~
kernel/panic.c:816:17: note: in expansion of macro 'pr_warn'
816 | pr_warn("WARNING: %s:%d at %pS, CPU#%d: %s/%d\n",
| ^~~~~~~
kernel/panic.c:822:58: error: 'struct task_struct' has no member named 'comm'; did you mean 'mm'?
822 | raw_smp_processor_id(), current->comm, current->pid);
| ^~~~
include/linux/printk.h:486:33: note: in definition of macro 'printk_index_wrap'
486 | _p_func(_fmt, ##__VA_ARGS__); \
| ^~~~~~~~~~~
include/linux/printk.h:567:9: note: in expansion of macro 'printk'
567 | printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
| ^~~~~~
kernel/panic.c:820:17: note: in expansion of macro 'pr_warn'
820 | pr_warn("WARNING: at %pS, CPU#%d: %s/%d\n",
| ^~~~~~~
--
In file included from include/asm-generic/bug.h:28,
from arch/x86/include/asm/bug.h:103,
from arch/x86/include/asm/alternative.h:9,
from arch/x86/include/asm/segment.h:6,
from arch/x86/include/asm/ptrace.h:5,
from arch/x86/include/asm/math_emu.h:5,
from arch/x86/include/asm/processor.h:13,
from include/linux/sched.h:13,
from include/linux/ratelimit.h:6,
from include/linux/dev_printk.h:16,
from include/linux/device.h:15,
from include/linux/node.h:18,
from include/linux/cpu.h:17,
from kernel/watchdog.c:15:
kernel/watchdog.c: In function 'watchdog_timer_fn':
>> kernel/watchdog.c:814:34: error: 'struct task_struct' has no member named 'comm'; did you mean 'mm'?
814 | current->comm, task_pid_nr(current));
| ^~~~
include/linux/printk.h:486:33: note: in definition of macro 'printk_index_wrap'
486 | _p_func(_fmt, ##__VA_ARGS__); \
| ^~~~~~~~~~~
include/linux/printk.h:527:9: note: in expansion of macro 'printk'
527 | printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
| ^~~~~~
kernel/watchdog.c:812:17: note: in expansion of macro 'pr_emerg'
812 | pr_emerg("BUG: soft lockup - CPU#%d stuck for %us! [%s:%d]\n",
| ^~~~~~~~
--
In file included from include/asm-generic/bug.h:28,
from arch/x86/include/asm/bug.h:103,
from arch/x86/include/asm/alternative.h:9,
from arch/x86/include/asm/segment.h:6,
from arch/x86/include/asm/ptrace.h:5,
from arch/x86/include/asm/math_emu.h:5,
from arch/x86/include/asm/processor.h:13,
from include/linux/sched.h:13,
from kernel/rseq.c:11:
kernel/rseq.c: In function 'rseq_validate_ro_fields':
>> kernel/rseq.c:65:36: error: 'struct task_struct' has no member named 'comm'; did you mean 'mm'?
65 | t->pid, t->comm,
| ^~~~
include/linux/printk.h:486:33: note: in definition of macro 'printk_index_wrap'
486 | _p_func(_fmt, ##__VA_ARGS__); \
| ^~~~~~~~~~~
include/linux/printk.h:567:9: note: in expansion of macro 'printk'
567 | printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
| ^~~~~~
kernel/rseq.c:60:17: note: in expansion of macro 'pr_warn'
60 | pr_warn("Detected rseq corruption for pid: %d, name: %s\n"
| ^~~~~~~
--
In file included from include/trace/define_trace.h:132,
from include/trace/events/task.h:98,
from kernel/fork.c:121:
include/trace/events/task.h: In function 'do_trace_event_raw_event_task_newtask':
>> include/trace/events/task.h:24:45: error: 'struct task_struct' has no member named 'comm'; did you mean 'mm'?
24 | memcpy(__entry->comm, task->comm, TASK_COMM_LEN);
| ^~~~
include/trace/trace_events.h:427:11: note: in definition of macro '__DECLARE_EVENT_CLASS'
427 | { assign; } \
| ^~~~~~
include/trace/trace_events.h:435:23: note: in expansion of macro 'PARAMS'
435 | PARAMS(assign), PARAMS(print)) \
| ^~~~~~
include/trace/trace_events.h:40:9: note: in expansion of macro 'DECLARE_EVENT_CLASS'
40 | DECLARE_EVENT_CLASS(name, \
| ^~~~~~~~~~~~~~~~~~~
include/trace/trace_events.h:44:30: note: in expansion of macro 'PARAMS'
44 | PARAMS(assign), \
| ^~~~~~
include/trace/events/task.h:9:1: note: in expansion of macro 'TRACE_EVENT'
9 | TRACE_EVENT(task_newtask,
| ^~~~~~~~~~~
include/trace/events/task.h:22:9: note: in expansion of macro 'TP_fast_assign'
22 | TP_fast_assign(
| ^~~~~~~~~~~~~~
include/linux/fortify-string.h:690:26: note: in expansion of macro '__fortify_memcpy_chk'
690 | #define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \
| ^~~~~~~~~~~~~~~~~~~~
include/linux/fortify-string.h:691:35: note: in expansion of macro '__struct_size'
691 | __struct_size(p), __struct_size(q), \
| ^~~~~~~~~~~~~
include/trace/events/task.h:24:17: note: in expansion of macro 'memcpy'
24 | memcpy(__entry->comm, task->comm, TASK_COMM_LEN);
| ^~~~~~
>> include/trace/events/task.h:24:45: error: 'struct task_struct' has no member named 'comm'; did you mean 'mm'?
24 | memcpy(__entry->comm, task->comm, TASK_COMM_LEN);
| ^~~~
include/trace/trace_events.h:427:11: note: in definition of macro '__DECLARE_EVENT_CLASS'
427 | { assign; } \
| ^~~~~~
include/trace/trace_events.h:435:23: note: in expansion of macro 'PARAMS'
435 | PARAMS(assign), PARAMS(print)) \
| ^~~~~~
include/trace/trace_events.h:40:9: note: in expansion of macro 'DECLARE_EVENT_CLASS'
40 | DECLARE_EVENT_CLASS(name, \
| ^~~~~~~~~~~~~~~~~~~
include/trace/trace_events.h:44:30: note: in expansion of macro 'PARAMS'
44 | PARAMS(assign), \
| ^~~~~~
include/trace/events/task.h:9:1: note: in expansion of macro 'TRACE_EVENT'
9 | TRACE_EVENT(task_newtask,
| ^~~~~~~~~~~
include/trace/events/task.h:22:9: note: in expansion of macro 'TP_fast_assign'
22 | TP_fast_assign(
| ^~~~~~~~~~~~~~
include/linux/fortify-string.h:690:26: note: in expansion of macro '__fortify_memcpy_chk'
690 | #define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \
| ^~~~~~~~~~~~~~~~~~~~
include/linux/fortify-string.h:692:35: note: in expansion of macro '__member_size'
692 | __member_size(p), __member_size(q), \
| ^~~~~~~~~~~~~
include/trace/events/task.h:24:17: note: in expansion of macro 'memcpy'
24 | memcpy(__entry->comm, task->comm, TASK_COMM_LEN);
| ^~~~~~
>> include/trace/events/task.h:24:45: error: 'struct task_struct' has no member named 'comm'; did you mean 'mm'?
24 | memcpy(__entry->comm, task->comm, TASK_COMM_LEN);
| ^~~~
include/trace/trace_events.h:427:11: note: in definition of macro '__DECLARE_EVENT_CLASS'
427 | { assign; } \
| ^~~~~~
include/trace/trace_events.h:435:23: note: in expansion of macro 'PARAMS'
435 | PARAMS(assign), PARAMS(print)) \
| ^~~~~~
include/trace/trace_events.h:40:9: note: in expansion of macro 'DECLARE_EVENT_CLASS'
40 | DECLARE_EVENT_CLASS(name, \
| ^~~~~~~~~~~~~~~~~~~
include/trace/trace_events.h:44:30: note: in expansion of macro 'PARAMS'
44 | PARAMS(assign), \
| ^~~~~~
include/trace/events/task.h:9:1: note: in expansion of macro 'TRACE_EVENT'
9 | TRACE_EVENT(task_newtask,
| ^~~~~~~~~~~
include/trace/events/task.h:22:9: note: in expansion of macro 'TP_fast_assign'
22 | TP_fast_assign(
| ^~~~~~~~~~~~~~
include/linux/fortify-string.h:690:26: note: in expansion of macro '__fortify_memcpy_chk'
690 | #define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \
| ^~~~~~~~~~~~~~~~~~~~
include/trace/events/task.h:24:17: note: in expansion of macro 'memcpy'
24 | memcpy(__entry->comm, task->comm, TASK_COMM_LEN);
| ^~~~~~
include/trace/events/task.h: In function 'do_trace_event_raw_event_task_rename':
include/trace/events/task.h:48:46: error: 'struct task_struct' has no member named 'comm'; did you mean 'mm'?
48 | memcpy(entry->oldcomm, task->comm, TASK_COMM_LEN);
| ^~~~
include/trace/trace_events.h:427:11: note: in definition of macro '__DECLARE_EVENT_CLASS'
427 | { assign; } \
| ^~~~~~
include/trace/trace_events.h:435:23: note: in expansion of macro 'PARAMS'
435 | PARAMS(assign), PARAMS(print)) \
| ^~~~~~
include/trace/trace_events.h:40:9: note: in expansion of macro 'DECLARE_EVENT_CLASS'
40 | DECLARE_EVENT_CLASS(name, \
| ^~~~~~~~~~~~~~~~~~~
include/trace/trace_events.h:44:30: note: in expansion of macro 'PARAMS'
44 | PARAMS(assign), \
| ^~~~~~
include/trace/events/task.h:35:1: note: in expansion of macro 'TRACE_EVENT'
35 | TRACE_EVENT(task_rename,
| ^~~~~~~~~~~
include/trace/events/task.h:47:9: note: in expansion of macro 'TP_fast_assign'
47 | TP_fast_assign(
| ^~~~~~~~~~~~~~
include/linux/fortify-string.h:690:26: note: in expansion of macro '__fortify_memcpy_chk'
690 | #define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \
| ^~~~~~~~~~~~~~~~~~~~
include/linux/fortify-string.h:691:35: note: in expansion of macro '__struct_size'
691 | __struct_size(p), __struct_size(q), \
| ^~~~~~~~~~~~~
include/trace/events/task.h:48:17: note: in expansion of macro 'memcpy'
48 | memcpy(entry->oldcomm, task->comm, TASK_COMM_LEN);
| ^~~~~~
include/trace/events/task.h:48:46: error: 'struct task_struct' has no member named 'comm'; did you mean 'mm'?
48 | memcpy(entry->oldcomm, task->comm, TASK_COMM_LEN);
| ^~~~
include/trace/trace_events.h:427:11: note: in definition of macro '__DECLARE_EVENT_CLASS'
427 | { assign; } \
| ^~~~~~
include/trace/trace_events.h:435:23: note: in expansion of macro 'PARAMS'
435 | PARAMS(assign), PARAMS(print)) \
| ^~~~~~
include/trace/trace_events.h:40:9: note: in expansion of macro 'DECLARE_EVENT_CLASS'
40 | DECLARE_EVENT_CLASS(name, \
| ^~~~~~~~~~~~~~~~~~~
include/trace/trace_events.h:44:30: note: in expansion of macro 'PARAMS'
44 | PARAMS(assign), \
| ^~~~~~
include/trace/events/task.h:35:1: note: in expansion of macro 'TRACE_EVENT'
35 | TRACE_EVENT(task_rename,
| ^~~~~~~~~~~
include/trace/events/task.h:47:9: note: in expansion of macro 'TP_fast_assign'
47 | TP_fast_assign(
| ^~~~~~~~~~~~~~
include/linux/fortify-string.h:690:26: note: in expansion of macro '__fortify_memcpy_chk'
690 | #define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \
| ^~~~~~~~~~~~~~~~~~~~
include/linux/fortify-string.h:692:35: note: in expansion of macro '__member_size'
692 | __member_size(p), __member_size(q), \
| ^~~~~~~~~~~~~
include/trace/events/task.h:48:17: note: in expansion of macro 'memcpy'
48 | memcpy(entry->oldcomm, task->comm, TASK_COMM_LEN);
| ^~~~~~
include/trace/events/task.h:48:46: error: 'struct task_struct' has no member named 'comm'; did you mean 'mm'?
48 | memcpy(entry->oldcomm, task->comm, TASK_COMM_LEN);
| ^~~~
include/trace/trace_events.h:427:11: note: in definition of macro '__DECLARE_EVENT_CLASS'
427 | { assign; } \
| ^~~~~~
include/trace/trace_events.h:435:23: note: in expansion of macro 'PARAMS'
435 | PARAMS(assign), PARAMS(print)) \
| ^~~~~~
include/trace/trace_events.h:40:9: note: in expansion of macro 'DECLARE_EVENT_CLASS'
40 | DECLARE_EVENT_CLASS(name, \
| ^~~~~~~~~~~~~~~~~~~
include/trace/trace_events.h:44:30: note: in expansion of macro 'PARAMS'
44 | PARAMS(assign), \
| ^~~~~~
include/trace/events/task.h:35:1: note: in expansion of macro 'TRACE_EVENT'
35 | TRACE_EVENT(task_rename,
| ^~~~~~~~~~~
include/trace/events/task.h:47:9: note: in expansion of macro 'TP_fast_assign'
47 | TP_fast_assign(
| ^~~~~~~~~~~~~~
include/linux/fortify-string.h:690:26: note: in expansion of macro '__fortify_memcpy_chk'
690 | #define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \
| ^~~~~~~~~~~~~~~~~~~~
include/trace/events/task.h:48:17: note: in expansion of macro 'memcpy'
48 | memcpy(entry->oldcomm, task->comm, TASK_COMM_LEN);
| ^~~~~~
In file included from include/trace/define_trace.h:133:
include/trace/events/task.h: In function 'do_perf_trace_task_newtask':
>> include/trace/events/task.h:24:45: error: 'struct task_struct' has no member named 'comm'; did you mean 'mm'?
24 | memcpy(__entry->comm, task->comm, TASK_COMM_LEN);
| ^~~~
include/trace/perf.h:51:11: note: in definition of macro '__DECLARE_EVENT_CLASS'
51 | { assign; } \
| ^~~~~~
include/trace/perf.h:67:23: note: in expansion of macro 'PARAMS'
67 | PARAMS(assign), PARAMS(print)) \
| ^~~~~~
include/trace/trace_events.h:40:9: note: in expansion of macro 'DECLARE_EVENT_CLASS'
40 | DECLARE_EVENT_CLASS(name, \
| ^~~~~~~~~~~~~~~~~~~
include/trace/trace_events.h:44:30: note: in expansion of macro 'PARAMS'
44 | PARAMS(assign), \
| ^~~~~~
include/trace/events/task.h:9:1: note: in expansion of macro 'TRACE_EVENT'
9 | TRACE_EVENT(task_newtask,
| ^~~~~~~~~~~
include/trace/events/task.h:22:9: note: in expansion of macro 'TP_fast_assign'
22 | TP_fast_assign(
| ^~~~~~~~~~~~~~
include/linux/fortify-string.h:690:26: note: in expansion of macro '__fortify_memcpy_chk'
690 | #define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \
| ^~~~~~~~~~~~~~~~~~~~
include/linux/fortify-string.h:691:35: note: in expansion of macro '__struct_size'
691 | __struct_size(p), __struct_size(q), \
| ^~~~~~~~~~~~~
include/trace/events/task.h:24:17: note: in expansion of macro 'memcpy'
24 | memcpy(__entry->comm, task->comm, TASK_COMM_LEN);
| ^~~~~~
>> include/trace/events/task.h:24:45: error: 'struct task_struct' has no member named 'comm'; did you mean 'mm'?
24 | memcpy(__entry->comm, task->comm, TASK_COMM_LEN);
| ^~~~
include/trace/perf.h:51:11: note: in definition of macro '__DECLARE_EVENT_CLASS'
51 | { assign; } \
| ^~~~~~
include/trace/perf.h:67:23: note: in expansion of macro 'PARAMS'
67 | PARAMS(assign), PARAMS(print)) \
| ^~~~~~
include/trace/trace_events.h:40:9: note: in expansion of macro 'DECLARE_EVENT_CLASS'
40 | DECLARE_EVENT_CLASS(name, \
| ^~~~~~~~~~~~~~~~~~~
include/trace/trace_events.h:44:30: note: in expansion of macro 'PARAMS'
44 | PARAMS(assign), \
| ^~~~~~
include/trace/events/task.h:9:1: note: in expansion of macro 'TRACE_EVENT'
9 | TRACE_EVENT(task_newtask,
| ^~~~~~~~~~~
include/trace/events/task.h:22:9: note: in expansion of macro 'TP_fast_assign'
22 | TP_fast_assign(
| ^~~~~~~~~~~~~~
include/linux/fortify-string.h:690:26: note: in expansion of macro '__fortify_memcpy_chk'
690 | #define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \
| ^~~~~~~~~~~~~~~~~~~~
include/linux/fortify-string.h:692:35: note: in expansion of macro '__member_size'
692 | __member_size(p), __member_size(q), \
| ^~~~~~~~~~~~~
include/trace/events/task.h:24:17: note: in expansion of macro 'memcpy'
24 | memcpy(__entry->comm, task->comm, TASK_COMM_LEN);
| ^~~~~~
>> include/trace/events/task.h:24:45: error: 'struct task_struct' has no member named 'comm'; did you mean 'mm'?
24 | memcpy(__entry->comm, task->comm, TASK_COMM_LEN);
| ^~~~
include/trace/perf.h:51:11: note: in definition of macro '__DECLARE_EVENT_CLASS'
51 | { assign; } \
| ^~~~~~
include/trace/perf.h:67:23: note: in expansion of macro 'PARAMS'
67 | PARAMS(assign), PARAMS(print)) \
| ^~~~~~
include/trace/trace_events.h:40:9: note: in expansion of macro 'DECLARE_EVENT_CLASS'
40 | DECLARE_EVENT_CLASS(name, \
| ^~~~~~~~~~~~~~~~~~~
include/trace/trace_events.h:44:30: note: in expansion of macro 'PARAMS'
44 | PARAMS(assign), \
| ^~~~~~
include/trace/events/task.h:9:1: note: in expansion of macro 'TRACE_EVENT'
9 | TRACE_EVENT(task_newtask,
| ^~~~~~~~~~~
include/trace/events/task.h:22:9: note: in expansion of macro 'TP_fast_assign'
22 | TP_fast_assign(
| ^~~~~~~~~~~~~~
include/linux/fortify-string.h:690:26: note: in expansion of macro '__fortify_memcpy_chk'
690 | #define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \
| ^~~~~~~~~~~~~~~~~~~~
include/trace/events/task.h:24:17: note: in expansion of macro 'memcpy'
24 | memcpy(__entry->comm, task->comm, TASK_COMM_LEN);
| ^~~~~~
include/trace/events/task.h: In function 'do_perf_trace_task_rename':
include/trace/events/task.h:48:46: error: 'struct task_struct' has no member named 'comm'; did you mean 'mm'?
48 | memcpy(entry->oldcomm, task->comm, TASK_COMM_LEN);
| ^~~~
include/trace/perf.h:51:11: note: in definition of macro '__DECLARE_EVENT_CLASS'
51 | { assign; } \
| ^~~~~~
include/trace/perf.h:67:23: note: in expansion of macro 'PARAMS'
67 | PARAMS(assign), PARAMS(print)) \
| ^~~~~~
include/trace/trace_events.h:40:9: note: in expansion of macro 'DECLARE_EVENT_CLASS'
40 | DECLARE_EVENT_CLASS(name, \
| ^~~~~~~~~~~~~~~~~~~
include/trace/trace_events.h:44:30: note: in expansion of macro 'PARAMS'
44 | PARAMS(assign), \
| ^~~~~~
include/trace/events/task.h:35:1: note: in expansion of macro 'TRACE_EVENT'
35 | TRACE_EVENT(task_rename,
| ^~~~~~~~~~~
include/trace/events/task.h:47:9: note: in expansion of macro 'TP_fast_assign'
47 | TP_fast_assign(
| ^~~~~~~~~~~~~~
include/linux/fortify-string.h:690:26: note: in expansion of macro '__fortify_memcpy_chk'
690 | #define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \
| ^~~~~~~~~~~~~~~~~~~~
include/linux/fortify-string.h:691:35: note: in expansion of macro '__struct_size'
691 | __struct_size(p), __struct_size(q), \
| ^~~~~~~~~~~~~
include/trace/events/task.h:48:17: note: in expansion of macro 'memcpy'
48 | memcpy(entry->oldcomm, task->comm, TASK_COMM_LEN);
| ^~~~~~
include/trace/events/task.h:48:46: error: 'struct task_struct' has no member named 'comm'; did you mean 'mm'?
48 | memcpy(entry->oldcomm, task->comm, TASK_COMM_LEN);
| ^~~~
include/trace/perf.h:51:11: note: in definition of macro '__DECLARE_EVENT_CLASS'
51 | { assign; } \
| ^~~~~~
include/trace/perf.h:67:23: note: in expansion of macro 'PARAMS'
67 | PARAMS(assign), PARAMS(print)) \
| ^~~~~~
include/trace/trace_events.h:40:9: note: in expansion of macro 'DECLARE_EVENT_CLASS'
40 | DECLARE_EVENT_CLASS(name, \
| ^~~~~~~~~~~~~~~~~~~
include/trace/trace_events.h:44:30: note: in expansion of macro 'PARAMS'
44 | PARAMS(assign), \
| ^~~~~~
include/trace/events/task.h:35:1: note: in expansion of macro 'TRACE_EVENT'
35 | TRACE_EVENT(task_rename,
| ^~~~~~~~~~~
include/trace/events/task.h:47:9: note: in expansion of macro 'TP_fast_assign'
47 | TP_fast_assign(
| ^~~~~~~~~~~~~~
include/linux/fortify-string.h:690:26: note: in expansion of macro '__fortify_memcpy_chk'
690 | #define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \
| ^~~~~~~~~~~~~~~~~~~~
include/linux/fortify-string.h:692:35: note: in expansion of macro '__member_size'
692 | __member_size(p), __member_size(q), \
| ^~~~~~~~~~~~~
include/trace/events/task.h:48:17: note: in expansion of macro 'memcpy'
48 | memcpy(entry->oldcomm, task->comm, TASK_COMM_LEN);
| ^~~~~~
include/trace/events/task.h:48:46: error: 'struct task_struct' has no member named 'comm'; did you mean 'mm'?
48 | memcpy(entry->oldcomm, task->comm, TASK_COMM_LEN);
| ^~~~
include/trace/perf.h:51:11: note: in definition of macro '__DECLARE_EVENT_CLASS'
51 | { assign; } \
| ^~~~~~
include/trace/perf.h:67:23: note: in expansion of macro 'PARAMS'
67 | PARAMS(assign), PARAMS(print)) \
| ^~~~~~
include/trace/trace_events.h:40:9: note: in expansion of macro 'DECLARE_EVENT_CLASS'
40 | DECLARE_EVENT_CLASS(name, \
| ^~~~~~~~~~~~~~~~~~~
include/trace/trace_events.h:44:30: note: in expansion of macro 'PARAMS'
..
vim +818 kernel/panic.c
bd89bb29a01503 Arjan van de Ven 2008-11-28 807
2553b67a1fbe7b Josh Poimboeuf 2016-03-17 808 void __warn(const char *file, int line, void *caller, unsigned taint,
2553b67a1fbe7b Josh Poimboeuf 2016-03-17 809 struct pt_regs *regs, struct warn_args *args)
0f6f49a8cd0163 Linus Torvalds 2009-05-16 810 {
4833794db61c8c Thomas Gleixner 2024-08-20 811 nbcon_cpu_emergency_enter();
4833794db61c8c Thomas Gleixner 2024-08-20 812
de7edd31457b62 Steven Rostedt (Red Hat 2013-06-14 813) disable_trace_on_warning();
de7edd31457b62 Steven Rostedt (Red Hat 2013-06-14 814)
1d1c158ece6cb7 Ingo Molnar 2025-05-15 815 if (file) {
1d1c158ece6cb7 Ingo Molnar 2025-05-15 816 pr_warn("WARNING: %s:%d at %pS, CPU#%d: %s/%d\n",
1d1c158ece6cb7 Ingo Molnar 2025-05-15 817 file, line, caller,
1d1c158ece6cb7 Ingo Molnar 2025-05-15 @818 raw_smp_processor_id(), current->comm, current->pid);
1d1c158ece6cb7 Ingo Molnar 2025-05-15 819 } else {
1d1c158ece6cb7 Ingo Molnar 2025-05-15 820 pr_warn("WARNING: at %pS, CPU#%d: %s/%d\n",
1d1c158ece6cb7 Ingo Molnar 2025-05-15 821 caller,
1d1c158ece6cb7 Ingo Molnar 2025-05-15 822 raw_smp_processor_id(), current->comm, current->pid);
1d1c158ece6cb7 Ingo Molnar 2025-05-15 823 }
74853dba2f7a1a Arjan van de Ven 2008-11-28 824
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH v5 3/3] treewide: Switch from tsk->comm to tsk->comm_str which is 64 bytes long
2025-07-16 20:47 ` Andrii Nakryiko
@ 2025-07-17 18:35 ` Linus Torvalds
2025-07-21 7:52 ` Bhupesh Sharma
0 siblings, 1 reply; 12+ messages in thread
From: Linus Torvalds @ 2025-07-17 18:35 UTC (permalink / raw)
To: Andrii Nakryiko
Cc: Bhupesh Sharma, Bhupesh, akpm, kernel-dev, linux-kernel, bpf,
linux-perf-users, linux-fsdevel, linux-mm, oliver.sang, lkp,
laoar.shao, pmladek, rostedt, mathieu.desnoyers, arnaldo.melo,
alexei.starovoitov, mirq-linux, peterz, willy, david, viro,
keescook, ebiederm, brauner, jack, mingo, juri.lelli, bsegall,
mgorman, vschneid, linux-trace-kernel, kees
On Wed, 16 Jul 2025 at 13:47, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote:
>
> But given how frequently task->comm is referenced (pretty much any
> profiler or tracer will capture this), it's just the widespread nature
> of accessing task->comm in BPF programs/scripts that will cause a lot
> of adaptation churn. And given the reason for renaming was to catch
> missing cases during refactoring, my ask was to do this renaming
> locally, validate all kernel code was modified, and then switch the
> field name back to "comm" (which you already did, so the remaining
> part would be just to rename comm_str back to comm).
Yes. Please.
Renaming the field is a great way to have the compiler scream loudly
of any missed cases, but keep it local (without committing it), and
rename it back after checking everything.
Then just talk about how every case has been checked in the commit message.
Linus
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH v5 3/3] treewide: Switch from tsk->comm to tsk->comm_str which is 64 bytes long
2025-07-17 18:35 ` Linus Torvalds
@ 2025-07-21 7:52 ` Bhupesh Sharma
0 siblings, 0 replies; 12+ messages in thread
From: Bhupesh Sharma @ 2025-07-21 7:52 UTC (permalink / raw)
To: Linus Torvalds, Andrii Nakryiko
Cc: Bhupesh, akpm, kernel-dev, linux-kernel, bpf, linux-perf-users,
linux-fsdevel, linux-mm, oliver.sang, lkp, laoar.shao, pmladek,
rostedt, mathieu.desnoyers, arnaldo.melo, alexei.starovoitov,
mirq-linux, peterz, willy, david, viro, keescook, ebiederm,
brauner, jack, mingo, juri.lelli, bsegall, mgorman, vschneid,
linux-trace-kernel, kees
Hi Linus,
On 7/18/25 12:05 AM, Linus Torvalds wrote:
> On Wed, 16 Jul 2025 at 13:47, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote:
>> But given how frequently task->comm is referenced (pretty much any
>> profiler or tracer will capture this), it's just the widespread nature
>> of accessing task->comm in BPF programs/scripts that will cause a lot
>> of adaptation churn. And given the reason for renaming was to catch
>> missing cases during refactoring, my ask was to do this renaming
>> locally, validate all kernel code was modified, and then switch the
>> field name back to "comm" (which you already did, so the remaining
>> part would be just to rename comm_str back to comm).
> Yes. Please.
>
> Renaming the field is a great way to have the compiler scream loudly
> of any missed cases, but keep it local (without committing it), and
> rename it back after checking everything.
>
>
Sure, I will send v6 with the above suggested change.
Thanks.
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH v5 3/3] treewide: Switch from tsk->comm to tsk->comm_str which is 64 bytes long
2025-07-16 12:39 ` [PATCH v5 3/3] treewide: Switch from tsk->comm to tsk->comm_str which is 64 bytes long Bhupesh
2025-07-16 18:10 ` Andrii Nakryiko
2025-07-17 4:23 ` kernel test robot
@ 2025-07-24 9:16 ` Askar Safin
2025-07-24 12:38 ` Bhupesh Sharma
2 siblings, 1 reply; 12+ messages in thread
From: Askar Safin @ 2025-07-24 9:16 UTC (permalink / raw)
To: bhupesh
Cc: akpm, alexei.starovoitov, andrii.nakryiko, arnaldo.melo, bpf,
brauner, bsegall, david, ebiederm, jack, juri.lelli, kees,
keescook, kernel-dev, laoar.shao, linux-fsdevel, linux-kernel,
linux-mm, linux-perf-users, linux-trace-kernel, lkp,
mathieu.desnoyers, mgorman, mingo, mirq-linux, oliver.sang,
peterz, pmladek, rostedt, torvalds, viro, vschneid, willy
> where TASK_COMM_EXT_LEN is 64-bytes.
Why 64? As well as I understand, comm is initialized from executable file name by default. And it is usually limited by 256 (or 255?) bytes. So, please, make limit 256 bytes.
--
Askar Safin
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH v5 3/3] treewide: Switch from tsk->comm to tsk->comm_str which is 64 bytes long
2025-07-24 9:16 ` Askar Safin
@ 2025-07-24 12:38 ` Bhupesh Sharma
0 siblings, 0 replies; 12+ messages in thread
From: Bhupesh Sharma @ 2025-07-24 12:38 UTC (permalink / raw)
To: Askar Safin, bhupesh
Cc: akpm, alexei.starovoitov, andrii.nakryiko, arnaldo.melo, bpf,
brauner, bsegall, david, ebiederm, jack, juri.lelli, kees,
keescook, kernel-dev, laoar.shao, linux-fsdevel, linux-kernel,
linux-mm, linux-perf-users, linux-trace-kernel, lkp,
mathieu.desnoyers, mgorman, mingo, mirq-linux, oliver.sang,
peterz, pmladek, rostedt, torvalds, viro, vschneid, willy
On 7/24/25 2:46 PM, Askar Safin wrote:
>> where TASK_COMM_EXT_LEN is 64-bytes.
> Why 64? As well as I understand, comm is initialized from executable file name by default. And it is usually limited by 256 (or 255?) bytes. So, please, make limit 256 bytes.
>
>
Check existing users like proc_task_name(), which use 64-byte comm names:
void proc_task_name(struct seq_file *m, struct task_struct *p, bool escape)
{
char tcomm[64];
....
Hence, it was decided not to change this and other similar existing
users and cap tsk->comm to 64-bytes.
Thanks,
Bhupesh
^ permalink raw reply [flat|nested] 12+ messages in thread
end of thread, other threads:[~2025-07-24 12:38 UTC | newest]
Thread overview: 12+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-07-16 12:39 [PATCH v5 0/3] Add support for long task name Bhupesh
2025-07-16 12:39 ` [PATCH v5 1/3] exec: Remove obsolete comments Bhupesh
2025-07-16 12:39 ` [PATCH v5 2/3] treewide: Switch memcpy() users of 'task->comm' to a more safer implementation Bhupesh
2025-07-16 12:39 ` [PATCH v5 3/3] treewide: Switch from tsk->comm to tsk->comm_str which is 64 bytes long Bhupesh
2025-07-16 18:10 ` Andrii Nakryiko
2025-07-16 20:18 ` Bhupesh Sharma
2025-07-16 20:47 ` Andrii Nakryiko
2025-07-17 18:35 ` Linus Torvalds
2025-07-21 7:52 ` Bhupesh Sharma
2025-07-17 4:23 ` kernel test robot
2025-07-24 9:16 ` Askar Safin
2025-07-24 12:38 ` Bhupesh Sharma
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