linux/fs/proc
Suren Baghdasaryan 49b0638502 mm: enable page walking API to lock vmas during the walk
walk_page_range() and friends often operate under write-locked mmap_lock. 
With introduction of vma locks, the vmas have to be locked as well during
such walks to prevent concurrent page faults in these areas.  Add an
additional member to mm_walk_ops to indicate locking requirements for the
walk.

The change ensures that page walks which prevent concurrent page faults
by write-locking mmap_lock, operate correctly after introduction of
per-vma locks.  With per-vma locks page faults can be handled under vma
lock without taking mmap_lock at all, so write locking mmap_lock would
not stop them.  The change ensures vmas are properly locked during such
walks.

A sample issue this solves is do_mbind() performing queue_pages_range()
to queue pages for migration.  Without this change a concurrent page
can be faulted into the area and be left out of migration.

Link: https://lkml.kernel.org/r/20230804152724.3090321-2-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Suggested-by: Jann Horn <jannh@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michel Lespinasse <michel@lespinasse.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21 13:07:20 -07:00
..
array.c Add support for new Linear Address Masking CPU feature. This is similar 2023-04-28 09:43:49 -07:00
base.c Mainly singleton patches all over the place. Series of note are: 2023-04-27 19:57:00 -07:00
bootconfig.c proc: bootconfig: Add null pointer check 2022-04-02 08:40:09 -04:00
cmdline.c proc: mark /proc/cmdline as permanent 2023-02-02 22:50:02 -08:00
consoles.c proc: consoles: use console_list_lock for list iteration 2022-12-02 11:25:02 +01:00
cpuinfo.c x86/aperfmperf: Replace aperfmperf_get_khz() 2022-04-27 20:22:19 +02:00
devices.c proc: mark more files as permanent 2022-10-03 14:21:45 -07:00
fd.c fs.idmapped.v6.3 2023-02-20 11:53:11 -08:00
fd.h fs: port ->permission() to pass mnt_idmap 2023-01-19 09:24:28 +01:00
generic.c proc: remove mark_inode_dirty() in .setattr() 2023-04-08 13:45:36 -07:00
inode.c tty, proc, kernfs, random: Use copy_splice_read() 2023-05-24 08:42:16 -06:00
internal.h fs: port ->getattr() to pass mnt_idmap 2023-01-19 09:24:25 +01:00
interrupts.c
Kconfig proc: make config PROC_CHILDREN depend on PROC_FS 2022-10-03 14:21:43 -07:00
kcore.c fs/proc/kcore: reinstate bounce buffer for KCORE_TEXT regions 2023-08-04 13:03:42 -07:00
kmsg.c printk changes for 6.1 2022-10-10 11:24:19 -07:00
loadavg.c proc: mark more files as permanent 2022-10-03 14:21:45 -07:00
Makefile
meminfo.c mm: Add support for unaccepted memory 2023-06-06 16:38:22 +02:00
namespaces.c Merge branch 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-01-29 11:20:24 -08:00
nommu.c proc: delete unused <linux/uaccess.h> includes 2022-07-17 17:31:39 -07:00
page.c mm, pagemap: remove SLOB and SLQB from comments and documentation 2023-03-29 10:32:11 +02:00
proc_net.c fs: port ->getattr() to pass mnt_idmap 2023-01-19 09:24:25 +01:00
proc_sysctl.c sysctl: set variable sysctl_mount_point storage-class-specifier to static 2023-06-30 16:19:47 -07:00
proc_tty.c proc: delete unused <linux/uaccess.h> includes 2022-07-17 17:31:39 -07:00
root.c fs: port ->getattr() to pass mnt_idmap 2023-01-19 09:24:25 +01:00
self.c Revert "proc: don't allow async path resolution of /proc/self components" 2021-02-23 20:32:11 -07:00
softirqs.c proc: mark more files as permanent 2022-10-03 14:21:45 -07:00
stat.c proc/stat: remove arch_idle_time() 2023-04-18 16:39:33 -07:00
task_mmu.c mm: enable page walking API to lock vmas during the walk 2023-08-21 13:07:20 -07:00
task_nommu.c mm: nommu: correct the range of mmap_sem_read_lock in task_mem() 2023-06-23 16:59:32 -07:00
thread_self.c Revert "proc: don't allow async path resolution of /proc/thread-self components" 2021-02-23 20:32:11 -07:00
uptime.c proc: mark more files as permanent 2022-10-03 14:21:45 -07:00
util.c
version.c proc: mark more files as permanent 2022-10-03 14:21:45 -07:00
vmcore.c proc/vmcore: fix signedness bug in read_from_oldmem() 2023-07-27 13:07:05 -07:00