Commit Graph

617887 Commits

Author SHA1 Message Date
Helge Deller 9e91db6b4a parisc: Add hardened usercopy feature
Add hardened usercopy checks to parisc architecture and clean up
indenting.

Signed-off-by: Helge Deller <deller@gmx.de>
2016-10-06 22:10:19 +02:00
Helge Deller f39cce654f parisc: Add cfi_startproc and cfi_endproc to assembly code
Add ENTRY_CFI() and ENDPROC_CFI() macros for dwarf debug info and
convert assembly users to new macros.

Signed-off-by: Helge Deller <deller@gmx.de>
2016-10-05 22:54:40 +02:00
Helge Deller 2929e73800 parisc: Move hpmc stack into page aligned bss section
Do not reserve space in data section for hpmc stack, instead move it
into the page aligned bss section.

Signed-off-by: Helge Deller <deller@gmx.de>
2016-10-05 22:54:29 +02:00
Helge Deller 92420bd0d0 parisc: Fix self-detected CPU stall warnings on Mako machines
The config option HAVE_UNSTABLE_SCHED_CLOCK is set automatically when compiling
for SMP. There is no need to clear the stable-clock flag via
clear_sched_clock_stable() when starting secondary CPUs, and even worse,
clearing it triggers wrong self-detected CPU stall warnings on 64bit Mako
machines.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # 4.7+
2016-09-25 21:27:01 +02:00
Helge Deller b391667eb4 parisc: Report trap type as human readable string
When faulting on some trap, the kernel currently reports in dmesg:

 do_page_fault() command='perl' type=6 address=0xbe400403 in libcrypt-2.24.so[f9086000+9000]
 vm_start = 0x00922000, vm_end = 0x00aed000

With this change the trap type additionally gets reported as human readable
string which makes it simpler to recognize the type of problem:

 do_page_fault() command='perl' type=6 address=0xbe400403 in libcrypt-2.24.so[f9086000+9000]
 trap #6: Instruction TLB miss fault, vm_start = 0x00922000, vm_end = 0x00aed000

Signed-off-by: Helge Deller <deller@gmx.de>
2016-09-24 21:45:46 +02:00
John David Anglin 910a86435d parisc: Update comment regarding implementation of copy_user_page_asm
The attached patch describes the current implementation of
copy_user_page_asm().  It is possible to implement this routine using
either the kernel page mappings or equivalent aliases.  I tested both
and decided the former was more efficient.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
2016-09-20 20:00:12 +02:00
Markus Elfring c4351d980e parisc: Use kmalloc_array() in add_system_map_addresses()
* A multiplication for the size determination of a memory allocation
  indicated that an array data structure should be processed.
  Thus use the corresponding function "kmalloc_array".

  This issue was detected by using the Coccinelle software.

* Replace the specification of a data type by a pointer dereference
  to make the corresponding size determination a bit safer according to
  the Linux coding style convention.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Helge Deller <deller@gmx.de>
2016-09-20 18:02:56 +02:00
Helge Deller 5baf919dd7 parisc: Check return value of smp_boot_one_cpu()
Check return value of smp_boot_one_cpu() whether CPU could be brought up.

Reported-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
2016-09-20 18:02:36 +02:00
Helge Deller b5d5cf2b8a parisc: Drop BROKEN_RODATA config option
PARISC was the only architecture which selected the BROKEN_RODATA config
option. Drop it and remove the special handling from init.h as well.

Signed-off-by: Helge Deller <deller@gmx.de>
2016-09-20 18:02:35 +02:00
Linus Torvalds d2ffb0103a Merge branch 'akpm' (patches from Andrew)
Merge fixes from Andrew Morton:
 "20 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  rapidio/rio_cm: avoid GFP_KERNEL in atomic context
  Revert "ocfs2: bump up o2cb network protocol version"
  ocfs2: fix start offset to ocfs2_zero_range_for_truncate()
  cgroup: duplicate cgroup reference when cloning sockets
  mm: memcontrol: make per-cpu charge cache IRQ-safe for socket accounting
  ocfs2: fix double unlock in case retry after free truncate log
  fanotify: fix list corruption in fanotify_get_response()
  fsnotify: add a way to stop queueing events on group shutdown
  ocfs2: fix trans extend while free cached blocks
  ocfs2: fix trans extend while flush truncate log
  ipc/shm: fix crash if CONFIG_SHMEM is not set
  mm: fix the page_swap_info() BUG_ON check
  autofs: use dentry flags to block walks during expire
  MAINTAINERS: update email for VLYNQ bus entry
  mm: avoid endless recursion in dump_page()
  mm, thp: fix leaking mapped pte in __collapse_huge_page_swapin()
  khugepaged: fix use-after-free in collapse_huge_page()
  MAINTAINERS: Maik has moved
  ocfs2/dlm: fix race between convert and migration
  mem-hotplug: don't clear the only node in new_node_page()
2016-09-19 16:08:03 -07:00
Alexandre Bounine b92ae139c3 rapidio/rio_cm: avoid GFP_KERNEL in atomic context
As reported by Alexey Khoroshilov (https://lkml.org/lkml/2016/9/9/737):
riocm_send_close() is called from rio_cm_shutdown() under
spin_lock_bh(idr_lock), but riocm_send_close() uses a GFP_KERNEL
allocation.

Fix by taking riocm_send_close() outside of spinlock protected code.

[akpm@linux-foundation.org: remove unneeded `if (!list_empty())']
Link: http://lkml.kernel.org/r/20160915175402.10122-1-alexandre.bounine@idt.com
Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Reported-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-19 15:36:17 -07:00
Junxiao Bi 63b52c4936 Revert "ocfs2: bump up o2cb network protocol version"
This reverts commit 38b52efd21 ("ocfs2: bump up o2cb network protocol
version").

This commit made rolling upgrade fail.  When one node is upgraded to new
version with this commit, the remaining nodes will fail to establish
connections to it, then the application like VMs on the remaining nodes
can't be live migrated to the upgraded one.  This will cause an outage.
Since negotiate hb timeout behavior didn't change without this commit,
so revert it.

Fixes: 38b52efd21 ("ocfs2: bump up o2cb network protocol version")
Link: http://lkml.kernel.org/r/1471396924-10375-1-git-send-email-junxiao.bi@oracle.com
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-19 15:36:17 -07:00
Ashish Samant d21c353d5e ocfs2: fix start offset to ocfs2_zero_range_for_truncate()
If we punch a hole on a reflink such that following conditions are met:

1. start offset is on a cluster boundary
2. end offset is not on a cluster boundary
3. (end offset is somewhere in another extent) or
   (hole range > MAX_CONTIG_BYTES(1MB)),

we dont COW the first cluster starting at the start offset.  But in this
case, we were wrongly passing this cluster to
ocfs2_zero_range_for_truncate() to zero out.  This will modify the
cluster in place and zero it in the source too.

Fix this by skipping this cluster in such a scenario.

To reproduce:

1. Create a random file of say 10 MB
     xfs_io -c 'pwrite -b 4k 0 10M' -f 10MBfile
2. Reflink  it
     reflink -f 10MBfile reflnktest
3. Punch a hole at starting at cluster boundary  with range greater that
1MB. You can also use a range that will put the end offset in another
extent.
     fallocate -p -o 0 -l 1048615 reflnktest
4. sync
5. Check the  first cluster in the source file. (It will be zeroed out).
    dd if=10MBfile iflag=direct bs=<cluster size> count=1 | hexdump -C

Link: http://lkml.kernel.org/r/1470957147-14185-1-git-send-email-ashish.samant@oracle.com
Signed-off-by: Ashish Samant <ashish.samant@oracle.com>
Reported-by: Saar Maoz <saar.maoz@oracle.com>
Reviewed-by: Srinivas Eeda <srinivas.eeda@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: Eric Ren <zren@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-19 15:36:17 -07:00
Johannes Weiner d979a39d72 cgroup: duplicate cgroup reference when cloning sockets
When a socket is cloned, the associated sock_cgroup_data is duplicated
but not its reference on the cgroup.  As a result, the cgroup reference
count will underflow when both sockets are destroyed later on.

Fixes: bd1060a1d6 ("sock, cgroup: add sock->sk_cgroup")
Link: http://lkml.kernel.org/r/20160914194846.11153-2-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: <stable@vger.kernel.org>	[4.5+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-19 15:36:17 -07:00
Johannes Weiner db2ba40c27 mm: memcontrol: make per-cpu charge cache IRQ-safe for socket accounting
During cgroup2 rollout into production, we started encountering css
refcount underflows and css access crashes in the memory controller.
Splitting the heavily shared css reference counter into logical users
narrowed the imbalance down to the cgroup2 socket memory accounting.

The problem turns out to be the per-cpu charge cache.  Cgroup1 had a
separate socket counter, but the new cgroup2 socket accounting goes
through the common charge path that uses a shared per-cpu cache for all
memory that is being tracked.  Those caches are safe against scheduling
preemption, but not against interrupts - such as the newly added packet
receive path.  When cache draining is interrupted by network RX taking
pages out of the cache, the resuming drain operation will put references
of in-use pages, thus causing the imbalance.

Disable IRQs during all per-cpu charge cache operations.

Fixes: f7e1cb6ec5 ("mm: memcontrol: account socket memory in unified hierarchy memory controller")
Link: http://lkml.kernel.org/r/20160914194846.11153-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: <stable@vger.kernel.org>	[4.5+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-19 15:36:17 -07:00
Joseph Qi 3bb8b653c8 ocfs2: fix double unlock in case retry after free truncate log
If ocfs2_reserve_cluster_bitmap_bits() fails with ENOSPC, it will try to
free truncate log and then retry.  Since ocfs2_try_to_free_truncate_log
will lock/unlock global bitmap inode, we have to unlock it before
calling this function.  But when retry reserve and it fails with no
global bitmap inode lock taken, it will unlock again in error handling
branch and BUG.

This issue also exists if no need retry and then ocfs2_inode_lock fails.
So fix it.

Fixes: 2070ad1aeb ("ocfs2: retry on ENOSPC if sufficient space in truncate log")
Link: http://lkml.kernel.org/r/57D91939.6030809@huawei.com
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Signed-off-by: Jiufei Xue <xuejiufei@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-19 15:36:17 -07:00
Jan Kara 96d41019e3 fanotify: fix list corruption in fanotify_get_response()
fanotify_get_response() calls fsnotify_remove_event() when it finds that
group is being released from fanotify_release() (bypass_perm is set).

However the event it removes need not be only in the group's notification
queue but it can have already moved to access_list (userspace read the
event before closing the fanotify instance fd) which is protected by a
different lock.  Thus when fsnotify_remove_event() races with
fanotify_release() operating on access_list, the list can get corrupted.

Fix the problem by moving all the logic removing permission events from
the lists to one place - fanotify_release().

Fixes: 5838d4442b ("fanotify: fix double free of pending permission events")
Link: http://lkml.kernel.org/r/1473797711-14111-3-git-send-email-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reported-by: Miklos Szeredi <mszeredi@redhat.com>
Tested-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-19 15:36:17 -07:00
Jan Kara 12703dbfeb fsnotify: add a way to stop queueing events on group shutdown
Implement a function that can be called when a group is being shutdown
to stop queueing new events to the group.  Fanotify will use this.

Fixes: 5838d4442b ("fanotify: fix double free of pending permission events")
Link: http://lkml.kernel.org/r/1473797711-14111-2-git-send-email-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-19 15:36:17 -07:00
Junxiao Bi d5bf141893 ocfs2: fix trans extend while free cached blocks
The root cause of this issue is the same with the one fixed by the last
patch, but this time credits for allocator inode and group descriptor
may not be consumed before trans extend.

The following error was caught:

  WARNING: CPU: 0 PID: 2037 at fs/jbd2/transaction.c:269 start_this_handle+0x4c3/0x510 [jbd2]()
  Modules linked in: ocfs2 nfsd lockd grace nfs_acl auth_rpcgss sunrpc autofs4 ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue configfs sd_mod sg ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables be2iscsi iscsi_boot_sysfs bnx2i cnic uio cxgb4i cxgb4 cxgb3i libcxgbi cxgb3 mdio ib_iser rdma_cm ib_cm iw_cm ib_sa ib_mad ib_core ib_addr ipv6 iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ppdev xen_kbdfront fb_sys_fops sysimgblt sysfillrect syscopyarea xen_netfront parport_pc parport pcspkr i2c_piix4 i2c_core acpi_cpufreq ext4 jbd2 mbcache xen_blkfront floppy pata_acpi ata_generic ata_piix dm_mirror dm_region_hash dm_log dm_mod
  CPU: 0 PID: 2037 Comm: rm Tainted: G        W       4.1.12-37.6.3.el6uek.bug24573128v2.x86_64 #2
  Hardware name: Xen HVM domU, BIOS 4.4.4OVM 02/11/2016
  Call Trace:
    dump_stack+0x48/0x5c
    warn_slowpath_common+0x95/0xe0
    warn_slowpath_null+0x1a/0x20
    start_this_handle+0x4c3/0x510 [jbd2]
    jbd2__journal_restart+0x161/0x1b0 [jbd2]
    jbd2_journal_restart+0x13/0x20 [jbd2]
    ocfs2_extend_trans+0x74/0x220 [ocfs2]
    ocfs2_free_cached_blocks+0x16b/0x4e0 [ocfs2]
    ocfs2_run_deallocs+0x70/0x270 [ocfs2]
    ocfs2_commit_truncate+0x474/0x6f0 [ocfs2]
    ocfs2_truncate_for_delete+0xbd/0x380 [ocfs2]
    ocfs2_wipe_inode+0x136/0x6a0 [ocfs2]
    ocfs2_delete_inode+0x2a2/0x3e0 [ocfs2]
    ocfs2_evict_inode+0x28/0x60 [ocfs2]
    evict+0xab/0x1a0
    iput_final+0xf6/0x190
    iput+0xc8/0xe0
    do_unlinkat+0x1b7/0x310
    SyS_unlinkat+0x22/0x40
    system_call_fastpath+0x12/0x71
  ---[ end trace a62437cb060baa71 ]---
  JBD2: rm wants too many credits (149 > 128)

Link: http://lkml.kernel.org/r/1473674623-11810-2-git-send-email-junxiao.bi@oracle.com
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-19 15:36:17 -07:00
Junxiao Bi 2b0ad0085a ocfs2: fix trans extend while flush truncate log
Every time, ocfs2_extend_trans() included a credit for truncate log
inode, but as that inode had been managed by jbd2 running transaction
first time, it will not consume that credit until
jbd2_journal_restart().

Since total credits to extend always included the un-consumed ones,
there will be more and more un-consumed credit, at last
jbd2_journal_restart() will fail due to credit number over the half of
max transction credit.

The following error was caught when unlinking a large file with many
extents:

  ------------[ cut here ]------------
  WARNING: CPU: 0 PID: 13626 at fs/jbd2/transaction.c:269 start_this_handle+0x4c3/0x510 [jbd2]()
  Modules linked in: ocfs2 nfsd lockd grace nfs_acl auth_rpcgss sunrpc autofs4 ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue configfs sd_mod sg ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables be2iscsi iscsi_boot_sysfs bnx2i cnic uio cxgb4i cxgb4 cxgb3i libcxgbi cxgb3 mdio ib_iser rdma_cm ib_cm iw_cm ib_sa ib_mad ib_core ib_addr ipv6 iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ppdev xen_kbdfront xen_netfront fb_sys_fops sysimgblt sysfillrect syscopyarea parport_pc parport pcspkr i2c_piix4 i2c_core acpi_cpufreq ext4 jbd2 mbcache xen_blkfront floppy pata_acpi ata_generic ata_piix dm_mirror dm_region_hash dm_log dm_mod
  CPU: 0 PID: 13626 Comm: unlink Tainted: G        W       4.1.12-37.6.3.el6uek.x86_64 #2
  Hardware name: Xen HVM domU, BIOS 4.4.4OVM 02/11/2016
  Call Trace:
    dump_stack+0x48/0x5c
    warn_slowpath_common+0x95/0xe0
    warn_slowpath_null+0x1a/0x20
    start_this_handle+0x4c3/0x510 [jbd2]
    jbd2__journal_restart+0x161/0x1b0 [jbd2]
    jbd2_journal_restart+0x13/0x20 [jbd2]
    ocfs2_extend_trans+0x74/0x220 [ocfs2]
    ocfs2_replay_truncate_records+0x93/0x360 [ocfs2]
    __ocfs2_flush_truncate_log+0x13e/0x3a0 [ocfs2]
    ocfs2_remove_btree_range+0x458/0x7f0 [ocfs2]
    ocfs2_commit_truncate+0x1b3/0x6f0 [ocfs2]
    ocfs2_truncate_for_delete+0xbd/0x380 [ocfs2]
    ocfs2_wipe_inode+0x136/0x6a0 [ocfs2]
    ocfs2_delete_inode+0x2a2/0x3e0 [ocfs2]
    ocfs2_evict_inode+0x28/0x60 [ocfs2]
    evict+0xab/0x1a0
    iput_final+0xf6/0x190
    iput+0xc8/0xe0
    do_unlinkat+0x1b7/0x310
    SyS_unlink+0x16/0x20
    system_call_fastpath+0x12/0x71
  ---[ end trace 28aa7410e69369cf ]---
  JBD2: unlink wants too many credits (251 > 128)

Link: http://lkml.kernel.org/r/1473674623-11810-1-git-send-email-junxiao.bi@oracle.com
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-19 15:36:17 -07:00
Kirill A. Shutemov 31b4beb473 ipc/shm: fix crash if CONFIG_SHMEM is not set
Commit c01d5b3007 ("shmem: get_unmapped_area align huge page") makes
use of shm_get_unmapped_area() in shm_file_operations() unconditional to
CONFIG_MMU.

As Tony Battersby pointed this can lead NULL-pointer dereference on
machine with CONFIG_MMU=y and CONFIG_SHMEM=n.  In this case ipc/shm is
backed by ramfs which doesn't provide f_op->get_unmapped_area for
configurations with MMU.

The solution is to provide dummy f_op->get_unmapped_area for ramfs when
CONFIG_MMU=y, which just call current->mm->get_unmapped_area().

Fixes: c01d5b3007 ("shmem: get_unmapped_area align huge page")
Link: http://lkml.kernel.org/r/20160912102704.140442-1-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Tony Battersby <tonyb@cybernetics.com>
Tested-by: Tony Battersby <tonyb@cybernetics.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org>	[4.7.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-19 15:36:17 -07:00
Santosh Shilimkar c8de641b1e mm: fix the page_swap_info() BUG_ON check
Commit 62c230bc17 ("mm: add support for a filesystem to activate
swap files and use direct_IO for writing swap pages") replaced the
swap_aops dirty hook from __set_page_dirty_no_writeback() with
swap_set_page_dirty().

For normal cases without these special SWP flags code path falls back to
__set_page_dirty_no_writeback() so the behaviour is expected to be the
same as before.

But swap_set_page_dirty() makes use of the page_swap_info() helper to
get the swap_info_struct to check for the flags like SWP_FILE,
SWP_BLKDEV etc as desired for those features.  This helper has
BUG_ON(!PageSwapCache(page)) which is racy and safe only for the
set_page_dirty_lock() path.

For the set_page_dirty() path which is often needed for cases to be
called from irq context, kswapd() can toggle the flag behind the back
while the call is getting executed when system is low on memory and
heavy swapping is ongoing.

This ends up with undesired kernel panic.

This patch just moves the check outside the helper to its users
appropriately to fix kernel panic for the described path.  Couple of
users of helpers already take care of SwapCache condition so I skipped
them.

Link: http://lkml.kernel.org/r/1473460718-31013-1-git-send-email-santosh.shilimkar@oracle.com
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Joe Perches <joe@perches.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Rik van Riel <riel@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jens Axboe <axboe@fb.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>	[4.7.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-19 15:36:17 -07:00
Ian Kent 7cbdb4a286 autofs: use dentry flags to block walks during expire
Somewhere along the way the autofs expire operation has changed to hold
a spin lock over expired dentry selection.  The autofs indirect mount
expired dentry selection is complicated and quite lengthy so it isn't
appropriate to hold a spin lock over the operation.

Commit 47be61845c ("fs/dcache.c: avoid soft-lockup in dput()") added a
might_sleep() to dput() causing a WARN_ONCE() about this usage to be
issued.

But the spin lock doesn't need to be held over this check, the autofs
dentry info.  flags are enough to block walks into dentrys during the
expire.

I've left the direct mount expire as it is (for now) because it is much
simpler and quicker than the indirect mount expire and adding spin lock
release and re-aquires would do nothing more than add overhead.

Fixes: 47be61845c ("fs/dcache.c: avoid soft-lockup in dput()")
Link: http://lkml.kernel.org/r/20160912014017.1773.73060.stgit@pluto.themaw.net
Signed-off-by: Ian Kent <raven@themaw.net>
Reported-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Takashi Iwai <tiwai@suse.de>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: NeilBrown <neilb@suse.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-19 15:36:17 -07:00
Florian Fainelli 08eeb3061e MAINTAINERS: update email for VLYNQ bus entry
Link: http://lkml.kernel.org/r/1473218738-21836-1-git-send-email-f.fainelli@gmail.com
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-19 15:36:17 -07:00
Kirill A. Shutemov 4d35427ad7 mm: avoid endless recursion in dump_page()
dump_page() uses page_mapcount() to get mapcount of the page.
page_mapcount() has VM_BUG_ON_PAGE(PageSlab(page)) as mapcount doesn't
make sense for slab pages and the field in struct page used for other
information.

It leads to recursion if dump_page() called for slub page and DEBUG_VM
is enabled:

dump_page() -> page_mapcount() -> VM_BUG_ON_PAGE() -> dump_page -> ...

Let's avoid calling page_mapcount() for slab pages in dump_page().

Link: http://lkml.kernel.org/r/20160908082137.131076-1-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-19 15:36:16 -07:00