linux.git/kernel/signal.c, branch v6.10-rc6

Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

2024-05-23T19:04:36+00:00

Pull virtio updates from Michael Tsirkin:
 "Several new features here:

   - virtio-net is finally supported in vduse

   - virtio (balloon and mem) interaction with suspend is improved

   - vhost-scsi now handles signals better/faster

  And fixes, cleanups all over the place"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (48 commits)
  virtio-pci: Check if is_avq is NULL
  virtio: delete vq in vp_find_vqs_msix() when request_irq() fails
  MAINTAINERS: add Eugenio Pérez as reviewer
  vhost-vdpa: Remove usage of the deprecated ida_simple_xx() API
  vp_vdpa: don't allocate unused msix vectors
  sound: virtio: drop owner assignment
  fuse: virtio: drop owner assignment
  scsi: virtio: drop owner assignment
  rpmsg: virtio: drop owner assignment
  nvdimm: virtio_pmem: drop owner assignment
  wifi: mac80211_hwsim: drop owner assignment
  vsock/virtio: drop owner assignment
  net: 9p: virtio: drop owner assignment
  net: virtio: drop owner assignment
  net: caif: virtio: drop owner assignment
  misc: nsm: drop owner assignment
  iommu: virtio: drop owner assignment
  drm/virtio: drop owner assignment
  gpio: virtio: drop owner assignment
  firmware: arm_scmi: virtio: drop owner assignment
  ...

kernel: Remove signal hacks for vhost_tasks

2024-05-22T12:31:15+00:00

This removes the signal/coredump hacks added for vhost_tasks in:

Commit f9010dbdce91 ("fork, vhost: Use CLONE_THREAD to fix freezer/ps regression")

When that patch was added vhost_tasks did not handle SIGKILL and would
try to ignore/clear the signal and continue on until the device's close
function was called. In the previous patches vhost_tasks and the vhost
drivers were converted to support SIGKILL by cleaning themselves up and
exiting. The hacks are no longer needed so this removes them.

Signed-off-by: Mike Christie 
Message-Id: <20240316004707.45557-10-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin

kernel misc: Remove the now superfluous sentinel elements from ctl_table array

2024-04-24T07:43:53+00:00

This commit comes at the tail end of a greater effort to remove the
empty elements at the end of the ctl_table arrays (sentinels) which
will reduce the overall build time size of the kernel and run time
memory bloat by ~64 bytes per sentinel (further information Link :
https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/)

Remove the sentinel from ctl_table arrays. Reduce by one the values used
to compare the size of the adjusted arrays.

Signed-off-by: Joel Granados

Merge tag 'mm-nonmm-stable-2024-03-14-09-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2024-03-15T01:03:09+00:00

Pull non-MM updates from Andrew Morton:

 - Kuan-Wei Chiu has developed the well-named series "lib min_heap: Min
   heap optimizations".

 - Kuan-Wei Chiu has also sped up the library sorting code in the series
   "lib/sort: Optimize the number of swaps and comparisons".

 - Alexey Gladkov has added the ability for code running within an IPC
   namespace to alter its IPC and MQ limits. The series is "Allow to
   change ipc/mq sysctls inside ipc namespace".

 - Geert Uytterhoeven has contributed some dhrystone maintenance work in
   the series "lib: dhry: miscellaneous cleanups".

 - Ryusuke Konishi continues nilfs2 maintenance work in the series

	"nilfs2: eliminate kmap and kmap_atomic calls"
	"nilfs2: fix kernel bug at submit_bh_wbc()"

 - Nathan Chancellor has updated our build tools requirements in the
   series "Bump the minimum supported version of LLVM to 13.0.1".

 - Muhammad Usama Anjum continues with the selftests maintenance work in
   the series "selftests/mm: Improve run_vmtests.sh".

 - Oleg Nesterov has done some maintenance work against the signal code
   in the series "get_signal: minor cleanups and fix".

Plus the usual shower of singleton patches in various parts of the tree.
Please see the individual changelogs for details.

* tag 'mm-nonmm-stable-2024-03-14-09-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (77 commits)
  nilfs2: prevent kernel bug at submit_bh_wbc()
  nilfs2: fix failure to detect DAT corruption in btree and direct mappings
  ocfs2: enable ocfs2_listxattr for special files
  ocfs2: remove SLAB_MEM_SPREAD flag usage
  assoc_array: fix the return value in assoc_array_insert_mid_shortcut()
  buildid: use kmap_local_page()
  watchdog/core: remove sysctl handlers from public header
  nilfs2: use div64_ul() instead of do_div()
  mul_u64_u64_div_u64: increase precision by conditionally swapping a and b
  kexec: copy only happens before uchunk goes to zero
  get_signal: don't initialize ksig->info if SIGNAL_GROUP_EXIT/group_exec_task
  get_signal: hide_si_addr_tag_bits: fix the usage of uninitialized ksig
  get_signal: don't abuse ksig->info.si_signo and ksig->sig
  const_structs.checkpatch: add device_type
  Normalise "name (ad@dr)" MODULE_AUTHORs to "name "
  dyndbg: replace kstrdup() + strchr() with kstrdup_and_replace()
  list: leverage list_is_head() for list_entry_is_head()
  nilfs2: MAINTAINERS: drop unreachable project mirror site
  smp: make __smp_processor_id() 0-argument macro
  fat: fix uninitialized field in nostale filehandles
  ...

get_signal: don't initialize ksig->info if SIGNAL_GROUP_EXIT/group_exec_task

2024-03-06T21:07:39+00:00

This initialization is incomplete and unnecessary, neither do_group_exit()
nor PF_USER_WORKER need ksig->info.

Link: https://lkml.kernel.org/r/20240226165653.GA20834@redhat.com
Signed-off-by: Oleg Nesterov 
Cc: Christian Brauner 
Cc: Eric W. Biederman 
Cc: Peter Collingbourne 
Cc: Wen Yang 
Signed-off-by: Andrew Morton

get_signal: hide_si_addr_tag_bits: fix the usage of uninitialized ksig

2024-03-06T21:07:39+00:00

ksig->ka and ksig->info are not initialized if get_signal() returns 0 or
if the caller is PF_USER_WORKER.

Check signr != 0 before SA_EXPOSE_TAGBITS and move the "out" label down.

The latter means that ksig->sig won't be initialized if a PF_USER_WORKER
thread gets a fatal signal but this is fine, PF_USER_WORKER's don't use
ksig. And there is nothing new, in this case ksig->ka and ksig-info are
not initialized anyway. Add a comment.

Link: https://lkml.kernel.org/r/20240226165650.GA20829@redhat.com
Signed-off-by: Oleg Nesterov 
Cc: Christian Brauner 
Cc: Eric W. Biederman 
Cc: Peter Collingbourne 
Cc: Wen Yang 
Signed-off-by: Andrew Morton

get_signal: don't abuse ksig->info.si_signo and ksig->sig

2024-03-06T21:07:39+00:00

Patch series "get_signal: minor cleanups and fix".

Lets remove this clear_siginfo() right now.  It is incomplete (and thus
looks confusing) and unnecessary.  Also, PF_USER_WORKER's already don't
get a fully initialized ksig anyway.


This patch (of 3):

Cleanup and preparation for the next changes.

get_signal() uses signr or ksig->info.si_signo or ksig->sig in a chaotic
way, this looks confusing. Change it to always use signr.

Link: https://lkml.kernel.org/r/20240226165612.GA20787@redhat.com
Link: https://lkml.kernel.org/r/20240226165647.GA20826@redhat.com
Signed-off-by: Oleg Nesterov 
Cc: Christian Brauner 
Cc: Eric W. Biederman 
Cc: Peter Collingbourne 
Cc: Wen Yang 
Signed-off-by: Andrew Morton

pidfd: allow to override signal scope in pidfd_send_signal()

2024-02-21T08:46:08+00:00

Right now we determine the scope of the signal based on the type of
pidfd. There are use-cases where it's useful to override the scope of
the signal. For example in [1]. Add flags to determine the scope of the
signal:

(1) PIDFD_SIGNAL_THREAD: send signal to specific thread reference by @pidfd
(2) PIDFD_SIGNAL_THREAD_GROUP: send signal to thread-group of @pidfd
(2) PIDFD_SIGNAL_PROCESS_GROUP: send signal to process-group of @pidfd

Since we now allow specifying PIDFD_SEND_PROCESS_GROUP for
pidfd_send_signal() to send signals to process groups we need to adjust
the check restricting si_code emulation by userspace to account for
PIDTYPE_PGID.

Reviewed-by: Oleg Nesterov 
Link: https://github.com/systemd/systemd/issues/31093 [1]
Link: https://lore.kernel.org/r/20240210-chihuahua-hinzog-3945b6abd44a@brauner
Link: https://lore.kernel.org/r/20240214123655.GB16265@redhat.com
Signed-off-by: Christian Brauner

pidfd: change pidfd_send_signal() to respect PIDFD_THREAD

2024-02-10T21:37:23+00:00

Turn kill_pid_info() into kill_pid_info_type(), this allows to pass any
pid_type to group_send_sig_info(), despite its name it should work fine
even if type = PIDTYPE_PID.

Change pidfd_send_signal() to use PIDTYPE_PID or PIDTYPE_TGID depending
on PIDFD_THREAD.

While at it kill another TODO comment in pidfd_show_fdinfo(). As Christian
expains fdinfo reports f_flags, userspace can already detect PIDFD_THREAD.

Reviewed-by: Tycho Andersen 
Signed-off-by: Oleg Nesterov 
Link: https://lore.kernel.org/r/20240209130650.GA8048@redhat.com
Signed-off-by: Christian Brauner

signal: fill in si_code in prepare_kill_siginfo()

2024-02-10T21:37:18+00:00

So that do_tkill() can use this helper too. This also simplifies
the next patch.

TODO: perhaps we can kill prepare_kill_siginfo() and change the
callers to use SEND_SIG_NOINFO,  but this needs some changes in
__send_signal_locked() and TP_STORE_SIGINFO().

Reviewed-by: Tycho Andersen 
Signed-off-by: Oleg Nesterov 
Link: https://lore.kernel.org/r/20240209130620.GA8039@redhat.com
Signed-off-by: Christian Brauner