Commit Graph

1122294 Commits

Author SHA1 Message Date
Wolfram Sang
512cb7e4c1 reiserfs: move from strlcpy with unused retval to strscpy
Follow the advice of the below link and prefer 'strscpy' in this
subsystem.  Conversion is 1:1 because the return value is not used. 
Generated by a coccinelle script.

Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Link: https://lkml.kernel.org/r/20220818210153.8095-1-wsa+renesas@sang-engineering.com
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:10 -07:00
Wolfram Sang
c97e21fe91 ocfs2: move from strlcpy with unused retval to strscpy
Follow the advice of the below link and prefer 'strscpy' in this
subsystem.  Conversion is 1:1 because the return value is not used. 
Generated by a coccinelle script.

Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Link: https://lkml.kernel.org/r/20220818210123.7637-4-wsa+renesas@sang-engineering.com
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:09 -07:00
Wolfram Sang
216e71f13c ia64: move from strlcpy with unused retval to strscpy
Follow the advice of the below link and prefer 'strscpy' in this
subsystem.  Conversion is 1:1 because the return value is not used. 
Generated by a coccinelle script.

Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Link: https://lkml.kernel.org/r/20220818205940.6216-1-wsa+renesas@sang-engineering.com
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:09 -07:00
Wolfram Sang
88040e67b9 alpha: move from strlcpy with unused retval to strscpy
Follow the advice of the below link and prefer 'strscpy' in this
subsystem.  Conversion is 1:1 because the return value is not used. 
Generated by a coccinelle script.

Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Link: https://lkml.kernel.org/r/20220818205936.6144-1-wsa+renesas@sang-engineering.com
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:09 -07:00
Uros Bizjak
e1d7c7609a bitops: use try_cmpxchg in set_mask_bits and bit_clear_unless
Use try_cmpxchg instead of cmpxchg (*ptr, old, new) == old in
set_mask_bits and bit_clear_unless.  x86 CMPXCHG instruction returns
success in ZF flag, so this change saves a compare after cmpxchg (and
related move instruction in front of cmpxchg).

Also, try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg
fails, enabling further code simplifications.

Link: https://lkml.kernel.org/r/20220822143851.3290-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:09 -07:00
Fabio M. De Francesco
21490eff12 hfs: replace kmap() with kmap_local_page() in btree.c
kmap() is being deprecated in favor of kmap_local_page().

Two main problems with kmap(): (1) It comes with an overhead as mapping
space is restricted and protected by a global lock for synchronization and
(2) it also requires global TLB invalidation when the kmap's pool wraps
and it might block when the mapping space is fully utilized until a slot
becomes available.

With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts). 
It is faster than kmap() in kernels with HIGHMEM enabled.  Furthermore,
the tasks can be preempted and, when they are scheduled to run again, the
kernel virtual addresses are restored and still valid.

Since its use in btree.c is safe everywhere, it should be preferred.

Therefore, replace kmap() with kmap_local_page() in btree.c.  Where
possible, use the suited standard helpers (memzero_page(), memcpy_page())
instead of open coding kmap_local_page() plus memset() or memcpy().

Tested in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with
HIGHMEM64GB enabled.

Link: https://lkml.kernel.org/r/20220821180400.8198-4-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Chaitanya Kulkarni <kch@nvidia.com>
Cc: Christian Brauner (Microsoft) <brauner@kernel.org>
Cc: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:09 -07:00
Fabio M. De Francesco
ca0ac8dfd3 hfs: replace kmap() with kmap_local_page() in bnode.c
kmap() is being deprecated in favor of kmap_local_page().

Two main problems with kmap(): (1) It comes with an overhead as mapping
space is restricted and protected by a global lock for synchronization and
(2) it also requires global TLB invalidation when the kmap's pool wraps
and it might block when the mapping space is fully utilized until a slot
becomes available.

With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts). 
It is faster than kmap() in kernels with HIGHMEM enabled.  Furthermore,
the tasks can be preempted and, when they are scheduled to run again, the
kernel virtual addresses are restored and still valid.

Since its use in bnode.c is safe everywhere, it should be preferred.

Therefore, replace kmap() with kmap_local_page() in bnode.c.  Where
possible, use the suited standard helpers (memzero_page(), memcpy_page())
instead of open coding kmap_local_page() plus memset() or memcpy().

Tested in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with
HIGHMEM64GB enabled.

Link: https://lkml.kernel.org/r/20220821180400.8198-3-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Chaitanya Kulkarni <kch@nvidia.com>
Cc: Christian Brauner (Microsoft) <brauner@kernel.org>
Cc: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:08 -07:00
Fabio M. De Francesco
d75e9a4bcc hfs: unmap the page in the "fail_page" label
Patch series "hfs: Replace kmap() with kmap_local_page()".

kmap() is being deprecated in favor of kmap_local_page().

There are two main problems with kmap(): (1) It comes with an overhead as
mapping space is restricted and protected by a global lock for
synchronization and (2) it also requires global TLB invalidation when the
kmaps pool wraps and it might block when the mapping space is fully
utilized until a slot becomes available.

With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts). 
It is faster than kmap() in kernels with HIGHMEM enabled.  Furthermore,
the tasks can be preempted and, when they are scheduled to run again, the
kernel virtual addresses are restored and still valid.

Since its use in fs/hfs is safe everywhere, it should be preferred.

Therefore, replace kmap() with kmap_local_page() in fs/hfs.  Where
possible, use the suited standard helpers (memzero_page(), memcpy_page())
instead of open coding kmap_local_page() plus memset() or memcpy().

Fix a bug due to a page being not unmapped if the code jumps to the
"fail_page" label (1/3).

Tested in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with
HIGHMEM64GB enabled.


This patch (of 3):

Several paths within hfs_btree_open() jump to the "fail_page" label where
put_page() is called while the page is still mapped.

Call kunmap() to unmap the page soon before put_page().

Link: https://lkml.kernel.org/r/20220821180400.8198-1-fmdefrancesco@gmail.com
Link: https://lkml.kernel.org/r/20220821180400.8198-2-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Chaitanya Kulkarni <kch@nvidia.com>
Cc: Christian Brauner (Microsoft) <brauner@kernel.org>
Cc: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Cc: Matthew Wilcox <willy@infradead.org>]
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:08 -07:00
Fabio M. De Francesco
948084f0f6 kexec: replace kmap() with kmap_local_page()
kmap() is being deprecated in favor of kmap_local_page().

There are two main problems with kmap(): (1) It comes with an overhead as
mapping space is restricted and protected by a global lock for
synchronization and (2) it also requires global TLB invalidation when the
kmap's pool wraps and it might block when the mapping space is fully
utilized until a slot becomes available.

With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts). 
It is faster than kmap() in kernels with HIGHMEM enabled.  Furthermore,
the tasks can be preempted and, when they are scheduled to run again, the
kernel virtual addresses are restored and are still valid.

Since its use in kexec_core.c is safe everywhere, it should be preferred.

Therefore, replace kmap() with kmap_local_page() in kexec_core.c.

Tested on a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with
HIGHMEM64GB enabled.

Link: https://lkml.kernel.org/r/20220821182519.9483-1-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Acked-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:08 -07:00
Uros Bizjak
da3f52ba35 iversion: use atomic64_try_cmpxchg)
Use atomic64_try_cmpxchg instead of
atomic64_cmpxchg (*ptr, old, new) == old in inode_set_max_iversion_raw,
inode_maybe_inc_version and inode_query_iversion. x86 CMPXCHG instruction
returns success in ZF flag, so this change saves a compare after cmpxchg
(and related move instruction in front of cmpxchg).

Also, try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg
fails, enabling further code simplifications.

The loop in inode_maybe_inc_iversion improves from:

    5563:	48 89 ca             	mov    %rcx,%rdx
    5566:	48 89 c8             	mov    %rcx,%rax
    5569:	48 83 e2 fe          	and    $0xfffffffffffffffe,%rdx
    556d:	48 83 c2 02          	add    $0x2,%rdx
    5571:	f0 48 0f b1 16       	lock cmpxchg %rdx,(%rsi)
    5576:	48 39 c1             	cmp    %rax,%rcx
    5579:	0f 84 85 fc ff ff    	je     5204 <...>
    557f:	48 89 c1             	mov    %rax,%rcx
    5582:	eb df                	jmp    5563 <...>

to:

    5563:	48 89 c2             	mov    %rax,%rdx
    5566:	48 83 e2 fe          	and    $0xfffffffffffffffe,%rdx
    556a:	48 83 c2 02          	add    $0x2,%rdx
    556e:	f0 48 0f b1 11       	lock cmpxchg %rdx,(%rcx)
    5573:	0f 84 8b fc ff ff    	je     5204 <...>
    5579:	eb e8                	jmp    5563 <...>

Link: https://lkml.kernel.org/r/20220821193011.88208-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:08 -07:00
Uros Bizjak
38ace0d513 aio: use atomic_try_cmpxchg in __get_reqs_available
Use atomic_try_cmpxchg instead of atomic_cmpxchg (*ptr, old, new) == old
in __get_reqs_available.  x86 CMPXCHG instruction returns success in ZF
flag, so this change saves a compare after cmpxchg (and related move
instruction in front of cmpxchg).

Also, atomic_try_cmpxchg implicitly assigns old *ptr value to "old" when
cmpxchg fails, enabling further code simplifications.

No functional change intended.

Link: https://lkml.kernel.org/r/20220714164851.3055-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:08 -07:00
Uros Bizjak
b0192296b4 buffer: use try_cmpxchg in discard_buffer
Use try_cmpxchg instead of cmpxchg (*ptr, old, new) == old in
discard_buffer.  x86 CMPXCHG instruction returns success in ZF flag, so
this change saves a compare after cmpxchg (and related move instruction in
front of cmpxchg).

Also, try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg
fails, enabling further code simplifications.

Note that the value from *ptr should be read using READ_ONCE to prevent
the compiler from merging, refetching or reordering the read.

No functional change intended.

Link: https://lkml.kernel.org/r/20220714171653.12128-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:07 -07:00
Uros Bizjak
693fc06e98 epoll: use try_cmpxchg in list_add_tail_lockless
Use try_cmpxchg instead of cmpxchg (*ptr, old, new) == old in
list_add_tail_lockless.  x86 CMPXCHG instruction returns success in ZF
flag, so this change saves a compare after cmpxchg (and related move
instruction in front of cmpxchg).

No functional change intended.

Link: https://lkml.kernel.org/r/20220714173255.12987-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:07 -07:00
Sergei Trofimovich
aa06a9bd85 ia64: fix clock_getres(CLOCK_MONOTONIC) to report ITC frequency
clock_gettime(CLOCK_MONOTONIC, &tp) is very precise on ia64 as it uses ITC
(similar to rdtsc on x86).  It's not quite a hrtimer as it is a few times
slower than 1ns.  Usually 2-3ns.

clock_getres(CLOCK_MONOTONIC, &res) never reflected that fact and reported
0.04s precision (1/HZ value).

In https://bugs.gentoo.org/596382 gstreamer's test suite failed loudly
when it noticed precision discrepancy.

Before the change:

    clock_getres(CLOCK_MONOTONIC, &res) reported 250Hz precision.

After the change:

    clock_getres(CLOCK_MONOTONIC, &res) reports ITC (400Mhz) precision.

The patch is based on matoro's fix. I added a bit of explanation why we
need to special-case arch-specific clock_getres().

[akpm@linux-foundation.org: coding-style cleanups]
Link: https://lkml.kernel.org/r/20220820181813.2275195-1-slyich@gmail.com
Signed-off-by: Sergei Trofimovich <slyich@gmail.com>
Cc: matoro <matoro_mailinglist_kernel@matoro.tk>
Cc: Émeric Maschino <emeric.maschino@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:07 -07:00
Minghao Chi
cba7543e15 fs/qnx6: delete unnecessary checks before brelse()
brelse() tests whether its argument is NULL and then returns immediately. 
Thus remove the tests which are not needed around the shown calls.

Link: https://lkml.kernel.org/r/20220819081819.96347-1-chi.minghao@zte.com.cn
Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn>
Reported-by: Zeal Robot <zealci@zte.com.cn>
Cc: CGEL ZTE <cgel.zte@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Minghao Chi <chi.minghao@zte.com.cn>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:07 -07:00
Kefeng Wang
2be9880dc8 kernel: exit: cleanup release_thread()
Only x86 has own release_thread(), introduce a new weak release_thread()
function to clean empty definitions in other ARCHs.

Link: https://lkml.kernel.org/r/20220819014406.32266-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Guo Ren <guoren@kernel.org>				[csky]
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Brian Cain <bcain@quicinc.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>			[powerpc]
Acked-by: Stafford Horne <shorne@gmail.com>			[openrisc]
Acked-by: Catalin Marinas <catalin.marinas@arm.com>		[arm64]
Acked-by: Huacai Chen <chenhuacai@kernel.org>			[LoongArch]
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Chris Zankel <chris@zankel.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Guo Ren <guoren@kernel.org> [csky]
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Xuerui Wang <kernel@xen0n.name>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:07 -07:00
Brian Foster
f4068af3a6 proc: save LOC in vsyscall test
Do one fork in vsyscall detection code and let SIGSEGV handler exit and
carry information to the parent saving LOC.

[adobriyan@gmail.com: redo original patch, delete unnecessary variables, minimise code changes]
Link: https://lkml.kernel.org/r/YvoWzAn5dlhF75xa@localhost.localdomain
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Tested-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:06 -07:00
Uros Bizjak
4f1d2a030d llist: use try_cmpxchg in llist_add_batch and llist_del_first
Use try_cmpxchg instead of cmpxchg (*ptr, old, new) == old in
llist_add_batch and llist_del_first.  x86 CMPXCHG instruction returns
success in ZF flag, so this change saves a compare after cmpxchg.

Also, try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg
fails, enabling further code simplifications.

No functional change intended.

Link: https://lkml.kernel.org/r/20220712144917.4497-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:06 -07:00
Valentin Schneider
05c6257433 panic, kexec: make __crash_kexec() NMI safe
Attempting to get a crash dump out of a debug PREEMPT_RT kernel via an NMI
panic() doesn't work.  The cause of that lies in the PREEMPT_RT definition
of mutex_trylock():

	if (IS_ENABLED(CONFIG_DEBUG_RT_MUTEXES) && WARN_ON_ONCE(!in_task()))
		return 0;

This prevents an nmi_panic() from executing the main body of
__crash_kexec() which does the actual kexec into the kdump kernel.  The
warning and return are explained by:

  6ce47fd961 ("rtmutex: Warn if trylock is called from hard/softirq context")
  [...]
  The reasons for this are:

      1) There is a potential deadlock in the slowpath

      2) Another cpu which blocks on the rtmutex will boost the task
	 which allegedly locked the rtmutex, but that cannot work
	 because the hard/softirq context borrows the task context.

Furthermore, grabbing the lock isn't NMI safe, so do away with kexec_mutex
and replace it with an atomic variable.  This is somewhat overzealous as
*some* callsites could keep using a mutex (e.g.  the sysfs-facing ones
like crash_shrink_memory()), but this has the benefit of involving a
single unified lock and preventing any future NMI-related surprises.

Tested by triggering NMI panics via:

  $ echo 1 > /proc/sys/kernel/panic_on_unrecovered_nmi
  $ echo 1 > /proc/sys/kernel/unknown_nmi_panic
  $ echo 1 > /proc/sys/kernel/panic

  $ ipmitool power diag

Link: https://lkml.kernel.org/r/20220630223258.4144112-3-vschneid@redhat.com
Fixes: 6ce47fd961 ("rtmutex: Warn if trylock is called from hard/softirq context")
Signed-off-by: Valentin Schneider <vschneid@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:06 -07:00
Valentin Schneider
7bb5da0d49 kexec: turn all kexec_mutex acquisitions into trylocks
Patch series "kexec, panic: Making crash_kexec() NMI safe", v4.


This patch (of 2):

Most acquistions of kexec_mutex are done via mutex_trylock() - those were
a direct "translation" from:

  8c5a1cf0ad ("kexec: use a mutex for locking rather than xchg()")

there have however been two additions since then that use mutex_lock():
crash_get_memory_size() and crash_shrink_memory().

A later commit will replace said mutex with an atomic variable, and
locking operations will become atomic_cmpxchg().  Rather than having those
mutex_lock() become while (atomic_cmpxchg(&lock, 0, 1)), turn them into
trylocks that can return -EBUSY on acquisition failure.

This does halve the printable size of the crash kernel, but that's still
neighbouring 2G for 32bit kernels which should be ample enough.

Link: https://lkml.kernel.org/r/20220630223258.4144112-1-vschneid@redhat.com
Link: https://lkml.kernel.org/r/20220630223258.4144112-2-vschneid@redhat.com
Signed-off-by: Valentin Schneider <vschneid@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:06 -07:00
Neel Natu
9847f21225 lib/cmdline: avoid page fault in next_arg
An argument list like "arg=val arg2 \"" can trigger a page fault if the
page pointed by 'args[0xffffffff]' is not mapped and potential memory
corruption otherwise (unlikely but possible if the bogus address is mapped
and contents happen to match the ascii value of the quote character).

The fix is to ensure that we load 'args[i-1]' only when (i > 0).

Prior to this commit the following command would trigger an
unhandled page fault in the kernel:

root@(none):/linus/fs/fat# insmod ./fat.ko  "foo=bar \""
[   33.870507] BUG: unable to handle page fault for address: ffff888204252608
[   33.872180] #PF: supervisor read access in kernel mode
[   33.873414] #PF: error_code(0x0000) - not-present page
[   33.874650] PGD 4401067 P4D 4401067 PUD 0
[   33.875321] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC PTI
[   33.876113] CPU: 16 PID: 399 Comm: insmod Not tainted 5.19.0-dbg-DEV #4
[   33.877193] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-debian-1.16.0-4 04/01/2014
[   33.878739] RIP: 0010:next_arg+0xd1/0x110
[   33.879399] Code: 22 75 1d 41 c6 04 01 00 41 80 f8 22 74 18 eb 35 4c 89 0e 45 31 d2 4c 89 cf 48 c7 02 00 00 00 00 41 80 f8 22 75 1f 41 8d 42 ff <41> 80 3c 01 22 75 14 41 c6 04 01 00 eb 0d 48 c7 02 00 00 00 00 41
[   33.882338] RSP: 0018:ffffc90001253d08 EFLAGS: 00010246
[   33.883174] RAX: 00000000ffffffff RBX: ffff888104252608 RCX: 0fc317bba1c1dd00
[   33.884311] RDX: ffffc90001253d40 RSI: ffffc90001253d48 RDI: ffff888104252609
[   33.885450] RBP: ffffc90001253d10 R08: 0000000000000022 R09: ffff888104252609
[   33.886595] R10: 0000000000000000 R11: ffffffff82c7ff20 R12: 0000000000000282
[   33.887748] R13: 00000000ffff8000 R14: 0000000000000000 R15: 0000000000007fff
[   33.888887] FS:  00007f04ec7432c0(0000) GS:ffff88813d300000(0000) knlGS:0000000000000000
[   33.890183] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   33.891111] CR2: ffff888204252608 CR3: 0000000100f36005 CR4: 0000000000170ee0
[   33.892241] Call Trace:
[   33.892641]  <TASK>
[   33.892989]  parse_args+0x8f/0x220
[   33.893538]  load_module+0x138b/0x15a0
[   33.894149]  ? prepare_coming_module+0x50/0x50
[   33.894879]  ? kernel_read_file_from_fd+0x5f/0x90
[   33.895639]  __se_sys_finit_module+0xce/0x130
[   33.896342]  __x64_sys_finit_module+0x1d/0x20
[   33.897042]  do_syscall_64+0x44/0xa0
[   33.897622]  entry_SYSCALL_64_after_hwframe+0x63/0xcd
[   33.898434] RIP: 0033:0x7f04ec85ef79
[   33.899009] Code: 48 8d 3d da db 0d 00 0f 05 eb a5 66 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d c7 9e 0d 00 f7 d8 64 89 01 48
[   33.901912] RSP: 002b:00007fffae81bfe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[   33.903081] RAX: ffffffffffffffda RBX: 0000559c5f1d2640 RCX: 00007f04ec85ef79
[   33.904191] RDX: 0000000000000000 RSI: 0000559c5f1d12a0 RDI: 0000000000000003
[   33.905304] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
[   33.906421] R10: 0000000000000003 R11: 0000000000000246 R12: 0000559c5f1d12a0
[   33.907526] R13: 0000000000000000 R14: 0000559c5f1d25f0 R15: 0000559c5f1d12a0
[   33.908631]  </TASK>
[   33.908986] Modules linked in: fat(+) [last unloaded: fat]
[   33.909843] CR2: ffff888204252608
[   33.910375] ---[ end trace 0000000000000000 ]---
[   33.911172] RIP: 0010:next_arg+0xd1/0x110
[   33.911796] Code: 22 75 1d 41 c6 04 01 00 41 80 f8 22 74 18 eb 35 4c 89 0e 45 31 d2 4c 89 cf 48 c7 02 00 00 00 00 41 80 f8 22 75 1f 41 8d 42 ff <41> 80 3c 01 22 75 14 41 c6 04 01 00 eb 0d 48 c7 02 00 00 00 00 41
[   33.914643] RSP: 0018:ffffc90001253d08 EFLAGS: 00010246
[   33.915446] RAX: 00000000ffffffff RBX: ffff888104252608 RCX: 0fc317bba1c1dd00
[   33.916544] RDX: ffffc90001253d40 RSI: ffffc90001253d48 RDI: ffff888104252609
[   33.917636] RBP: ffffc90001253d10 R08: 0000000000000022 R09: ffff888104252609
[   33.918727] R10: 0000000000000000 R11: ffffffff82c7ff20 R12: 0000000000000282
[   33.919821] R13: 00000000ffff8000 R14: 0000000000000000 R15: 0000000000007fff
[   33.920908] FS:  00007f04ec7432c0(0000) GS:ffff88813d300000(0000) knlGS:0000000000000000
[   33.922125] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   33.923017] CR2: ffff888204252608 CR3: 0000000100f36005 CR4: 0000000000170ee0
[   33.924098] Kernel panic - not syncing: Fatal exception
[   33.925776] Kernel Offset: disabled
[   33.926347] Rebooting in 10 seconds..

Link: https://lkml.kernel.org/r/20220728232434.1666488-1-neelnatu@google.com
Signed-off-by: Neel Natu <neelnatu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:06 -07:00
Ira Weiny
defdaff15a checkpatch: add kmap and kmap_atomic to the deprecated list
kmap() and kmap_atomic() are being deprecated in favor of
kmap_local_page().

There are two main problems with kmap(): (1) It comes with an overhead as
mapping space is restricted and protected by a global lock for
synchronization and (2) it also requires global TLB invalidation when the
kmap's pool wraps and it might block when the mapping space is fully
utilized until a slot becomes available.

kmap_local_page() is safe from any context and is therefore redundant with
kmap_atomic() with the exception of any pagefault or preemption disable
requirements.  However, using kmap_atomic() for these side effects makes
the code less clear.  So any requirement for pagefault or preemption
disable should be made explicitly.

With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts). 
It is faster than kmap() in kernels with HIGHMEM enabled.  Furthermore,
the tasks can be preempted and, when they are scheduled to run again, the
kernel virtual addresses are restored.

Link: https://lkml.kernel.org/r/20220813220034.806698-1-ira.weiny@intel.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Suggested-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:06 -07:00
Fabio M. De Francesco
5bb6ce3aeb fs/isofs: replace kmap() with kmap_local_page()
The use of kmap() is being deprecated in favor of kmap_local_page().

There are two main problems with kmap(): (1) It comes with an overhead as
mapping space is restricted and protected by a global lock for
synchronization and (2) it also requires global TLB invalidation when the
kmap's pool wraps and it might block when the mapping space is fully
utilized until a slot becomes available.

With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts). 
Tasks can be preempted and, when scheduled to run again, the kernel
virtual addresses are restored and still valid.  It is faster than kmap()
in kernels with HIGHMEM enabled.

Since kmap_local_page() can be safely used in compress.c, it should be
called everywhere instead of kmap().

Therefore, replace kmap() with kmap_local_page() in compress.c.  Where it
is needed, use memzero_page() instead of open coding kmap_local_page()
plus memset() to fill the pages with zeros.  Delete the redundant
flush_dcache_page() in the two call sites of memzero_page().

Tested with mkisofs on a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel
with HIGHMEM64GB enabled.

Link: https://lkml.kernel.org/r/20220801122709.8164-1-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Pali Rohár <pali@kernel.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:05 -07:00
Arnd Bergmann
64367f2e4f treewide: defconfig: address renamed CONFIG_DEBUG_INFO=y
CONFIG_DEBUG_INFO is now implicitly selected if one picks one of the
explicit options that could be DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT,
DEBUG_INFO_DWARF4, DEBUG_INFO_DWARF5.

This was actually not what I had in mind when I suggested making it a
'choice' statement, but it's too late to change again now, and the Kconfig
logic is more sensible in the new form.

Change any defconfig file that had CONFIG_DEBUG_INFO enabled but did not
pick DWARF4 or DWARF5 explicitly to now pick the toolchain default.

Link: https://lkml.kernel.org/r/20220811114609.2097335-1-arnd@kernel.org
Fixes: f9b3cd2457 ("Kconfig.debug: make DEBUG_INFO selectable from a choice")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Cc: Rich Felker <dalias@libc.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:05 -07:00
Manfred Spraul
58b5c20336 ipc/util.c: cleanup and improve sysvipc_find_ipc()
sysvipc_find_ipc() can be simplified further:

- It uses a for() loop to locate the next entry in the idr.
  This can be replaced with idr_get_next().

- It receives two parameters (pos - which is actually
  an idr index and not a position, and new_pos, which
  is really a position).
  One parameter is sufficient.

Link: https://lore.kernel.org/all/20210903052020.3265-3-manfred@colorfullife.com/
Link: https://lkml.kernel.org/r/20220805115733.104763-1-manfred@colorfullife.com
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Acked-by: Davidlohr Bueso <dave@stgolabs.net>
Acked-by: Waiman Long <longman@redhat.com>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: <1vier1@web.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:05 -07:00
Borislav Petkov
765f2bf04f scripts/decodecode: improve faulting line determination
There are cases where the IP pointer in a Code: line in an oops doesn't
point at the beginning of an instruction:

Code: 0f bd c2 e9 a0 cd b5 e4 48 0f bd c2 e9 97 cd b5 e4 0f 1f 80 00 00 00 00 \
	  e9 8b cd b5 e4 0f 1f 00 66 0f a3 d0 e9 7f cd b5 e4 0f 1f <80> 00 00 00 \
	  00 0f a3 d0 e9 70 cd b5 e4 48 0f a3 d0 e9 67 cd b5

  e9 7f cd b5 e4          jmp    0xffffffffe4b5cda8
  0f 1f 80 00 00 00 00    nopl   0x0(%rax)
	^^

and the current way of determining the faulting instruction line doesn't
work because disassembled instructions are counted from the IP byte to
the end and when that thing points in the middle, the trailing bytes can
be interpreted as different insns:

  Code starting with the faulting instruction
  ===========================================
     0:   80 00 00                addb   $0x0,(%rax)
     3:   00 00                   add    %al,(%rax)

whereas, this is part of

0f 1f 80 00 00 00 00    nopl   0x0(%rax)

     5:   0f a3 d0                bt     %edx,%eax
     ...

leading to:

  1d:   0f 1f 00                nopl   (%rax)
  20:   66 0f a3 d0             bt     %dx,%ax
  24:*  e9 7f cd b5 e4          jmp    0xffffffffe4b5cda8               <-- trapping instruction
  29:   0f 1f 80 00 00 00 00    nopl   0x0(%rax)
  30:   0f a3 d0                bt     %edx,%eax

which is the wrong faulting instruction.

Change the way the faulting line number is determined by matching the
opcode bytes from the beginning, leading to correct output:

  1d:   0f 1f 00                nopl   (%rax)
  20:   66 0f a3 d0             bt     %dx,%ax
  24:   e9 7f cd b5 e4          jmp    0xffffffffe4b5cda8
  29:*  0f 1f 80 00 00 00 00    nopl   0x0(%rax)                <-- trapping instruction
  30:   0f a3 d0                bt     %edx,%eax

While at it, make decodecode use bash as the interpreter - that thing
should be present on everything by now. It simplifies the code a lot
too.

Link: https://lkml.kernel.org/r/20220808085928.29840-1-bp@alien8.de
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:05 -07:00
Fabio M. De Francesco
9f25f357c5 hfsplus: convert kmap() to kmap_local_page() in btree.c
kmap() is being deprecated in favor of kmap_local_page().

There are two main problems with kmap(): (1) It comes with an overhead as
mapping space is restricted and protected by a global lock for
synchronization and (2) it also requires global TLB invalidation when the
kmap's pool wraps and it might block when the mapping space is fully
utilized until a slot becomes available.

With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts). 
It is faster than kmap() in kernels with HIGHMEM enabled.  Furthermore,
the tasks can be preempted and, when they are scheduled to run again, the
kernel virtual addresses are restored and are still valid.

Since its use in btree.c is safe everywhere, it should be preferred.

Therefore, replace kmap() with kmap_local_page() in btree.c.

Tested in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with
HIGHMEM64GB enabled.

Link: https://lkml.kernel.org/r/20220809203105.26183-5-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:05 -07:00
Fabio M. De Francesco
f9ef3b95a3 hfsplus: convert kmap() to kmap_local_page() in bitmap.c
kmap() is being deprecated in favor of kmap_local_page().

There are two main problems with kmap(): (1) It comes with an overhead as
mapping space is restricted and protected by a global lock for
synchronization and (2) it also requires global TLB invalidation when the
kmap's pool wraps and it might block when the mapping space is fully
utilized until a slot becomes available.

With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts). 
It is faster than kmap() in kernels with HIGHMEM enabled.  Furthermore,
the tasks can be preempted and, when they are scheduled to run again, the
kernel virtual addresses are restored and are still valid.

Since its use in bitmap.c is safe everywhere, it should be preferred.

Therefore, replace kmap() with kmap_local_page() in bitmap.c.

Tested in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with
HIGHMEM64GB enabled.

Link: https://lkml.kernel.org/r/20220809203105.26183-4-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:04 -07:00
Fabio M. De Francesco
6c3014a67a hfsplus: convert kmap() to kmap_local_page() in bnode.c
kmap() is being deprecated in favor of kmap_local_page().

Two main problems with kmap(): (1) It comes with an overhead as mapping
space is restricted and protected by a global lock for synchronization and
(2) it also requires global TLB invalidation when the kmap's pool wraps
and it might block when the mapping space is fully utilized until a slot
becomes available.

With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts). 
It is faster than kmap() in kernels with HIGHMEM enabled.  Furthermore,
the tasks can be preempted and, when they are scheduled to run again, the
kernel virtual addresses are restored and still valid.

Since its use in bnode.c is safe everywhere, it should be preferred.

Therefore, replace kmap() with kmap_local_page() in bnode.c.  Where
possible, use the suited standard helpers (memzero_page(), memcpy_page())
instead of open coding kmap_local_page() plus memset() or memcpy().

Tested in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with
HIGHMEM64GB enabled.

Link: https://lkml.kernel.org/r/20220809203105.26183-3-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:04 -07:00
Fabio M. De Francesco
f5b23d6704 hfsplus: unmap the page in the "fail_page" label
Patch series "hfsplus: Replace kmap() with kmap_local_page()".

kmap() is being deprecated in favor of kmap_local_page().

There are two main problems with kmap(): (1) It comes with an overhead as
mapping space is restricted and protected by a global lock for
synchronization and (2) it also requires global TLB invalidation when the
kmap’s pool wraps and it might block when the mapping space is fully
utilized until a slot becomes available.

With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts). 
It is faster than kmap() in kernels with HIGHMEM enabled.  Furthermore,
the tasks can be preempted and, when they are scheduled to run again, the
kernel virtual addresses are restored and still valid.

Since its use in fs/hfsplus is safe everywhere, it should be preferred.

Therefore, replace kmap() with kmap_local_page() in fs/hfsplus.  Where
possible, use the suited standard helpers (memzero_page(), memcpy_page())
instead of open coding kmap_local_page() plus memset() or memcpy().

Fix a bug due to a page being not unmapped if the code jumps to the
"fail_page" label (1/4).

Tested in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with
HIGHMEM64GB enabled.


This patch (of 4):

Several paths within hfs_btree_open() jump to the "fail_page" label where
put_page() is called while the page is still mapped.

Call kunmap() to unmap the page soon before put_page().

Link: https://lkml.kernel.org/r/20220809203105.26183-1-fmdefrancesco@gmail.com
Link: https://lkml.kernel.org/r/20220809203105.26183-2-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:04 -07:00
Linus Torvalds
b90cb10531 Linux 6.0-rc3 2022-08-28 15:05:29 -07:00
Linus Torvalds
b467192ec7 Seventeen hotfixes. Mostly memory management things. Ten patches are
cc:stable, addressing pre-6.0 issues.
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Merge tag 'mm-hotfixes-stable-2022-08-28' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull more hotfixes from Andrew Morton:
 "Seventeen hotfixes.  Mostly memory management things.

  Ten patches are cc:stable, addressing pre-6.0 issues"

* tag 'mm-hotfixes-stable-2022-08-28' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  .mailmap: update Luca Ceresoli's e-mail address
  mm/mprotect: only reference swap pfn page if type match
  squashfs: don't call kmalloc in decompressors
  mm/damon/dbgfs: avoid duplicate context directory creation
  mailmap: update email address for Colin King
  asm-generic: sections: refactor memory_intersects
  bootmem: remove the vmemmap pages from kmemleak in put_page_bootmem
  ocfs2: fix freeing uninitialized resource on ocfs2_dlm_shutdown
  Revert "memcg: cleanup racy sum avoidance code"
  mm/zsmalloc: do not attempt to free IS_ERR handle
  binder_alloc: add missing mmap_lock calls when using the VMA
  mm: re-allow pinning of zero pfns (again)
  vmcoreinfo: add kallsyms_num_syms symbol
  mailmap: update Guilherme G. Piccoli's email addresses
  writeback: avoid use-after-free after removing device
  shmem: update folio if shmem_replace_page() updates the page
  mm/hugetlb: avoid corrupting page->mapping in hugetlb_mcopy_atomic_pte
2022-08-28 14:49:59 -07:00
Linus Torvalds
373eff576e bitmap fixes for v6.0-rc3
Hi Linus,
 
 Please pull (hopefully) the last portion of fixes from Sander for his
 UP rework series. The original series came from -mm tree, and it was
 not the latest version, that's why we need follow-ups. It fixes only
 a test introduced by that series. The test fails under certain configs.
 
 From Sander:
 
 This series fixes the reported issues, and implements the suggested
 improvements, for the version of the cpumask tests [1] that was merged
 with commit c41e8866c2 ("lib/test: introduce cpumask KUnit test
 suite").
 
 These changes include fixes for the tests, and better alignment with the
 KUnit style guidelines.
 
 Thanks,
 Yury
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Merge tag 'bitmap-6.0-rc3' of github.com:/norov/linux

Pull bitmap fixes from Yury Norov:
 "Fix the reported issues, and implements the suggested improvements,
  for the version of the cpumask tests [1] that was merged with commit
  c41e8866c2 ("lib/test: introduce cpumask KUnit test suite").

  These changes include fixes for the tests, and better alignment with
  the KUnit style guidelines"

* tag 'bitmap-6.0-rc3' of github.com:/norov/linux:
  lib/cpumask_kunit: add tests file to MAINTAINERS
  lib/cpumask_kunit: log mask contents
  lib/test_cpumask: follow KUnit style guidelines
  lib/test_cpumask: fix cpu_possible_mask last test
  lib/test_cpumask: drop cpu_possible_mask full test
2022-08-28 14:36:27 -07:00
Luca Ceresoli
0ebafe2ea8 .mailmap: update Luca Ceresoli's e-mail address
My Bootlin address is preferred from now on.

Link: https://lkml.kernel.org/r/20220826130515.3011951-1-luca.ceresoli@bootlin.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Atish Patra <atishp@atishpatra.org>
Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-28 14:02:46 -07:00
Peter Xu
3d2f78f08c mm/mprotect: only reference swap pfn page if type match
Yu Zhao reported a bug after the commit "mm/swap: Add swp_offset_pfn() to
fetch PFN from swap entry" added a check in swp_offset_pfn() for swap type [1]:

  kernel BUG at include/linux/swapops.h:117!
  CPU: 46 PID: 5245 Comm: EventManager_De Tainted: G S         O L 6.0.0-dbg-DEV #2
  RIP: 0010:pfn_swap_entry_to_page+0x72/0xf0
  Code: c6 48 8b 36 48 83 fe ff 74 53 48 01 d1 48 83 c1 08 48 8b 09 f6
  c1 01 75 7b 66 90 48 89 c1 48 8b 09 f6 c1 01 74 74 5d c3 eb 9e <0f> 0b
  48 ba ff ff ff ff 03 00 00 00 eb ae a9 ff 0f 00 00 75 13 48
  RSP: 0018:ffffa59e73fabb80 EFLAGS: 00010282
  RAX: 00000000ffffffe8 RBX: 0c00000000000000 RCX: ffffcd5440000000
  RDX: 1ffffffffff7a80a RSI: 0000000000000000 RDI: 0c0000000000042b
  RBP: ffffa59e73fabb80 R08: ffff9965ca6e8bb8 R09: 0000000000000000
  R10: ffffffffa5a2f62d R11: 0000030b372e9fff R12: ffff997b79db5738
  R13: 000000000000042b R14: 0c0000000000042b R15: 1ffffffffff7a80a
  FS:  00007f549d1bb700(0000) GS:ffff99d3cf680000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000440d035b3180 CR3: 0000002243176004 CR4: 00000000003706e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   <TASK>
   change_pte_range+0x36e/0x880
   change_p4d_range+0x2e8/0x670
   change_protection_range+0x14e/0x2c0
   mprotect_fixup+0x1ee/0x330
   do_mprotect_pkey+0x34c/0x440
   __x64_sys_mprotect+0x1d/0x30

It triggers because pfn_swap_entry_to_page() could be called upon e.g. a
genuine swap entry.

Fix it by only calling it when it's a write migration entry where the page*
is used.

[1] https://lore.kernel.org/lkml/CAOUHufaVC2Za-p8m0aiHw6YkheDcrO-C3wRGixwDS32VTS+k1w@mail.gmail.com/

Link: https://lkml.kernel.org/r/20220823221138.45602-1-peterx@redhat.com
Fixes: 6c287605fd ("mm: remember exclusively mapped anonymous pages with PG_anon_exclusive")
Signed-off-by: Peter Xu <peterx@redhat.com>
Reported-by: Yu Zhao <yuzhao@google.com>
Tested-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-28 14:02:46 -07:00
Phillip Lougher
1f13dff09f squashfs: don't call kmalloc in decompressors
The decompressors may be called while in an atomic section.  So move the
kmalloc() out of this path, and into the "page actor" init function.

This fixes a regression introduced by commit
f268eedddf ("squashfs: extend "page actor" to handle missing pages")

Link: https://lkml.kernel.org/r/20220822215430.15933-1-phillip@squashfs.org.uk
Fixes: f268eedddf ("squashfs: extend "page actor" to handle missing pages")
Reported-by: Chris Murphy <lists@colorremedies.com>
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-28 14:02:45 -07:00
Badari Pulavarty
d26f607036 mm/damon/dbgfs: avoid duplicate context directory creation
When user tries to create a DAMON context via the DAMON debugfs interface
with a name of an already existing context, the context directory creation
fails but a new context is created and added in the internal data
structure, due to absence of the directory creation success check.  As a
result, memory could leak and DAMON cannot be turned on.  An example test
case is as below:

    # cd /sys/kernel/debug/damon/
    # echo "off" >  monitor_on
    # echo paddr > target_ids
    # echo "abc" > mk_context
    # echo "abc" > mk_context
    # echo $$ > abc/target_ids
    # echo "on" > monitor_on  <<< fails

Return value of 'debugfs_create_dir()' is expected to be ignored in
general, but this is an exceptional case as DAMON feature is depending
on the debugfs functionality and it has the potential duplicate name
issue.  This commit therefore fixes the issue by checking the directory
creation failure and immediately return the error in the case.

Link: https://lkml.kernel.org/r/20220821180853.2400-1-sj@kernel.org
Fixes: 75c1c2b53c ("mm/damon/dbgfs: support multiple contexts")
Signed-off-by: Badari Pulavarty <badari.pulavarty@intel.com>
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org>	[ 5.15.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-28 14:02:45 -07:00
Colin Ian King
ac733f6558 mailmap: update email address for Colin King
Colin King is working on kernel janitorial fixes in his spare time and
using his Intel email is confusing.  Use his gmail account as the default
email address.

Link: https://lkml.kernel.org/r/20220817212753.101109-1-colin.i.king@gmail.com
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-28 14:02:45 -07:00
Quanyang Wang
0c7d7cc2b4 asm-generic: sections: refactor memory_intersects
There are two problems with the current code of memory_intersects:

First, it doesn't check whether the region (begin, end) falls inside the
region (virt, vend), that is (virt < begin && vend > end).

The second problem is if vend is equal to begin, it will return true but
this is wrong since vend (virt + size) is not the last address of the
memory region but (virt + size -1) is.  The wrong determination will
trigger the misreporting when the function check_for_illegal_area calls
memory_intersects to check if the dma region intersects with stext region.

The misreporting is as below (stext is at 0x80100000):
 WARNING: CPU: 0 PID: 77 at kernel/dma/debug.c:1073 check_for_illegal_area+0x130/0x168
 DMA-API: chipidea-usb2 e0002000.usb: device driver maps memory from kernel text or rodata [addr=800f0000] [len=65536]
 Modules linked in:
 CPU: 1 PID: 77 Comm: usb-storage Not tainted 5.19.0-yocto-standard #5
 Hardware name: Xilinx Zynq Platform
  unwind_backtrace from show_stack+0x18/0x1c
  show_stack from dump_stack_lvl+0x58/0x70
  dump_stack_lvl from __warn+0xb0/0x198
  __warn from warn_slowpath_fmt+0x80/0xb4
  warn_slowpath_fmt from check_for_illegal_area+0x130/0x168
  check_for_illegal_area from debug_dma_map_sg+0x94/0x368
  debug_dma_map_sg from __dma_map_sg_attrs+0x114/0x128
  __dma_map_sg_attrs from dma_map_sg_attrs+0x18/0x24
  dma_map_sg_attrs from usb_hcd_map_urb_for_dma+0x250/0x3b4
  usb_hcd_map_urb_for_dma from usb_hcd_submit_urb+0x194/0x214
  usb_hcd_submit_urb from usb_sg_wait+0xa4/0x118
  usb_sg_wait from usb_stor_bulk_transfer_sglist+0xa0/0xec
  usb_stor_bulk_transfer_sglist from usb_stor_bulk_srb+0x38/0x70
  usb_stor_bulk_srb from usb_stor_Bulk_transport+0x150/0x360
  usb_stor_Bulk_transport from usb_stor_invoke_transport+0x38/0x440
  usb_stor_invoke_transport from usb_stor_control_thread+0x1e0/0x238
  usb_stor_control_thread from kthread+0xf8/0x104
  kthread from ret_from_fork+0x14/0x2c

Refactor memory_intersects to fix the two problems above.

Before the 1d7db834a0 ("dma-debug: use memory_intersects()
directly"), memory_intersects is called only by printk_late_init:

printk_late_init -> init_section_intersects ->memory_intersects.

There were few places where memory_intersects was called.

When commit 1d7db834a0 ("dma-debug: use memory_intersects()
directly") was merged and CONFIG_DMA_API_DEBUG is enabled, the DMA
subsystem uses it to check for an illegal area and the calltrace above
is triggered.

[akpm@linux-foundation.org: fix nearby comment typo]
Link: https://lkml.kernel.org/r/20220819081145.948016-1-quanyang.wang@windriver.com
Fixes: 9795593625 ("asm/sections: add helpers to check for section data")
Signed-off-by: Quanyang Wang <quanyang.wang@windriver.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Thierry Reding <treding@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-28 14:02:45 -07:00
Liu Shixin
dd0ff4d12d bootmem: remove the vmemmap pages from kmemleak in put_page_bootmem
The vmemmap pages is marked by kmemleak when allocated from memblock. 
Remove it from kmemleak when freeing the page.  Otherwise, when we reuse
the page, kmemleak may report such an error and then stop working.

 kmemleak: Cannot insert 0xffff98fb6eab3d40 into the object search tree (overlaps existing)
 kmemleak: Kernel memory leak detector disabled
 kmemleak: Object 0xffff98fb6be00000 (size 335544320):
 kmemleak:   comm "swapper", pid 0, jiffies 4294892296
 kmemleak:   min_count = 0
 kmemleak:   count = 0
 kmemleak:   flags = 0x1
 kmemleak:   checksum = 0
 kmemleak:   backtrace:

Link: https://lkml.kernel.org/r/20220819094005.2928241-1-liushixin2@huawei.com
Fixes: f41f2ed43c (mm: hugetlb: free the vmemmap pages associated with each HugeTLB page)
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-28 14:02:45 -07:00
Heming Zhao
550842cc60 ocfs2: fix freeing uninitialized resource on ocfs2_dlm_shutdown
After commit 0737e01de9 ("ocfs2: ocfs2_mount_volume does cleanup job
before return error"), any procedure after ocfs2_dlm_init() fails will
trigger crash when calling ocfs2_dlm_shutdown().

ie: On local mount mode, no dlm resource is initialized.  If
ocfs2_mount_volume() fails in ocfs2_find_slot(), error handling will call
ocfs2_dlm_shutdown(), then does dlm resource cleanup job, which will
trigger kernel crash.

This solution should bypass uninitialized resources in
ocfs2_dlm_shutdown().

Link: https://lkml.kernel.org/r/20220815085754.20417-1-heming.zhao@suse.com
Fixes: 0737e01de9 ("ocfs2: ocfs2_mount_volume does cleanup job before return error")
Signed-off-by: Heming Zhao <heming.zhao@suse.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-28 14:02:45 -07:00
Shakeel Butt
dbb16df644 Revert "memcg: cleanup racy sum avoidance code"
This reverts commit 96e51ccf1a.

Recently we started running the kernel with rstat infrastructure on
production traffic and begin to see negative memcg stats values. 
Particularly the 'sock' stat is the one which we observed having negative
value.

$ grep "sock " /mnt/memory/job/memory.stat
sock 253952
total_sock 18446744073708724224

Re-run after couple of seconds

$ grep "sock " /mnt/memory/job/memory.stat
sock 253952
total_sock 53248

For now we are only seeing this issue on large machines (256 CPUs) and
only with 'sock' stat.  I think the networking stack increase the stat on
one cpu and decrease it on another cpu much more often.  So, this negative
sock is due to rstat flusher flushing the stats on the CPU that has seen
the decrement of sock but missed the CPU that has increments.  A typical
race condition.

For easy stable backport, revert is the most simple solution.  For long
term solution, I am thinking of two directions.  First is just reduce the
race window by optimizing the rstat flusher.  Second is if the reader sees
a negative stat value, force flush and restart the stat collection. 
Basically retry but limited.

Link: https://lkml.kernel.org/r/20220817172139.3141101-1-shakeelb@google.com
Fixes: 96e51ccf1a ("memcg: cleanup racy sum avoidance code")
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Cc: "Michal Koutný" <mkoutny@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: <stable@vger.kernel.org>	[5.15]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-28 14:02:44 -07:00
Sergey Senozhatsky
a5d2172180 mm/zsmalloc: do not attempt to free IS_ERR handle
zsmalloc() now returns ERR_PTR values as handles, which zram accidentally
can pass to zs_free().  Another bad scenario is when zcomp_compress()
fails - handle has default -ENOMEM value, and zs_free() will try to free
that "pointer value".

Add the missing check and make sure that zs_free() bails out when
ERR_PTR() is passed to it.

Link: https://lkml.kernel.org/r/20220816050906.2583956-1-senozhatsky@chromium.org
Fixes: c7e6f17b52 ("zsmalloc: zs_malloc: return ERR_PTR on failure")
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>,
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-28 14:02:44 -07:00
Liam Howlett
44e602b4e5 binder_alloc: add missing mmap_lock calls when using the VMA
Take the mmap_read_lock() when using the VMA in binder_alloc_print_pages()
and when checking for a VMA in binder_alloc_new_buf_locked().

It is worth noting binder_alloc_new_buf_locked() drops the VMA read lock
after it verifies a VMA exists, but may be taken again deeper in the call
stack, if necessary.

Link: https://lkml.kernel.org/r/20220810160209.1630707-1-Liam.Howlett@oracle.com
Fixes: a43cfc87ca (android: binder: stop saving a pointer to the VMA)
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reported-by: Ondrej Mosnacek <omosnace@redhat.com>
Reported-by: <syzbot+a7b60a176ec13cafb793@syzkaller.appspotmail.com>
Acked-by: Carlos Llamas <cmllamas@google.com>
Tested-by: Ondrej Mosnacek <omosnace@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Christian Brauner (Microsoft) <brauner@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hridya Valsaraju <hridya@google.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Martijn Coenen <maco@android.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Todd Kjos <tkjos@android.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: "Arve Hjønnevåg" <arve@android.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-28 14:02:44 -07:00
Alex Williamson
fcab34b433 mm: re-allow pinning of zero pfns (again)
The below referenced commit makes the same error as 1c56343258 ("mm: fix
is_pinnable_page against a cma page"), re-interpreting the logic to
exclude pinning of the zero page, which breaks device assignment with
vfio.

To avoid further subtle mistakes, split the logic into discrete tests.

[akpm@linux-foundation.org: simplify comment, per John]
Link: https://lkml.kernel.org/r/166015037385.760108.16881097713975517242.stgit@omen
Link: https://lore.kernel.org/all/165490039431.944052.12458624139225785964.stgit@omen
Fixes: f25cbb7a95 ("mm: add zone device coherent type memory support")
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Suggested-by: Felix Kuehling <felix.kuehling@amd.com>
Tested-by: Slawomir Laba <slawomirx.laba@intel.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Cc: Alex Sierra <alex.sierra@amd.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Alistair Popple <apopple@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-28 14:02:44 -07:00
Stephen Brennan
f09bddbd86 vmcoreinfo: add kallsyms_num_syms symbol
The rest of the kallsyms symbols are useless without knowing the number of
symbols in the table.  In an earlier patch, I somehow dropped the
kallsyms_num_syms symbol, so add it back in.

Link: https://lkml.kernel.org/r/20220808205410.18590-1-stephen.s.brennan@oracle.com
Fixes: 5fd8fea935 ("vmcoreinfo: include kallsyms symbols")
Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-28 14:02:44 -07:00
Guilherme G. Piccoli
6c26d17eea mailmap: update Guilherme G. Piccoli's email addresses
Both @canonical and @ibm email addresses are invalid now; use my personal
address instead.

Link: https://lkml.kernel.org/r/20220804202207.439427-1-gpiccoli@igalia.com
Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-28 14:02:43 -07:00
Khazhismel Kumykov
f87904c075 writeback: avoid use-after-free after removing device
When a disk is removed, bdi_unregister gets called to stop further
writeback and wait for associated delayed work to complete.  However,
wb_inode_writeback_end() may schedule bandwidth estimation dwork after
this has completed, which can result in the timer attempting to access the
just freed bdi_writeback.

Fix this by checking if the bdi_writeback is alive, similar to when
scheduling writeback work.

Since this requires wb->work_lock, and wb_inode_writeback_end() may get
called from interrupt, switch wb->work_lock to an irqsafe lock.

Link: https://lkml.kernel.org/r/20220801155034.3772543-1-khazhy@google.com
Fixes: 45a2966fd6 ("writeback: fix bandwidth estimate for spiky workload")
Signed-off-by: Khazhismel Kumykov <khazhy@google.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Michael Stapelberg <stapelberg+linux@google.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-28 14:02:43 -07:00
Matthew Wilcox (Oracle)
9dfb3b8d65 shmem: update folio if shmem_replace_page() updates the page
If we allocate a new page, we need to make sure that our folio matches
that new page.

If we do end up in this code path, we store the wrong page in the shmem
inode's page cache, and I would rather imagine that data corruption
ensues.

This will be solved by changing shmem_replace_page() to
shmem_replace_folio(), but this is the minimal fix.

Link: https://lkml.kernel.org/r/20220730042518.1264767-1-willy@infradead.org
Fixes: da08e9b793 ("mm/shmem: convert shmem_swapin_page() to shmem_swapin_folio()")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-28 14:02:43 -07:00
Miaohe Lin
ab74ef708d mm/hugetlb: avoid corrupting page->mapping in hugetlb_mcopy_atomic_pte
In MCOPY_ATOMIC_CONTINUE case with a non-shared VMA, pages in the page
cache are installed in the ptes.  But hugepage_add_new_anon_rmap is called
for them mistakenly because they're not vm_shared.  This will corrupt the
page->mapping used by page cache code.

Link: https://lkml.kernel.org/r/20220712130542.18836-1-linmiaohe@huawei.com
Fixes: f619147104 ("userfaultfd: add UFFDIO_CONTINUE ioctl")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-28 14:02:43 -07:00