[tree-wide] finally take no_llseek out

no_llseek had been defined to NULL two years ago, in commit 868941b14441
("fs: remove no_llseek")

To quote that commit,

At -rc1 we'll need do a mechanical

[tree-wide] finally take no_llseek out

no_llseek had been defined to NULL two years ago, in commit 868941b14441
("fs: remove no_llseek")

To quote that commit,

At -rc1 we'll need do a mechanical removal of no_llseek -

git grep -l -w no_llseek | grep -v porting.rst | while read i; do
sed -i '/\<no_llseek\>/d' $i
done

would do it.

Unfortunately, that hadn't been done. Linus, could you do that now, so
that we could finally put that thing to rest? All instances are of the
form
.llseek = no_llseek,
so it's obviously safe.

Signed-off-by: Al Viro <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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PM: hibernate: Don't ignore return from set_memory_ro()

set_memory_ro() and set_memory_rw() can fail, leaving memory
unprotected.

Take the returned value into account and abort in case of
failure.

PM: hibernate: Don't ignore return from set_memory_ro()

set_memory_ro() and set_memory_rw() can fail, leaving memory
unprotected.

Take the returned value into account and abort in case of
failure.

Signed-off-by: Christophe Leroy <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

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freezer: Have {,un}lock_system_sleep() save/restore flags

Rafael explained that the reason for having both PF_NOFREEZE and
PF_FREEZER_SKIP is that {,un}lock_system_sleep() is callable from
kthread c

freezer: Have {,un}lock_system_sleep() save/restore flags

Rafael explained that the reason for having both PF_NOFREEZE and
PF_FREEZER_SKIP is that {,un}lock_system_sleep() is callable from
kthread context that has previously called set_freezable().

In preparation of merging the flags, have {,un}lock_system_slee() save
and restore current->flags.

Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Acked-by: Rafael J. Wysocki <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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PM: hibernate: defer device probing when resuming from hibernation

syzbot is reporting hung task at misc_open() [1], for there is a race
window of AB-BA deadlock which involves probe_count variable.

PM: hibernate: defer device probing when resuming from hibernation

syzbot is reporting hung task at misc_open() [1], for there is a race
window of AB-BA deadlock which involves probe_count variable. Currently
wait_for_device_probe() from snapshot_open() from misc_open() can sleep
forever with misc_mtx held if probe_count cannot become 0.

When a device is probed by hub_event() work function, probe_count is
incremented before the probe function starts, and probe_count is
decremented after the probe function completed.

There are three cases that can prevent probe_count from dropping to 0.

(a) A device being probed stopped responding (i.e. broken/malicious
hardware).

(b) A process emulating a USB device using /dev/raw-gadget interface
stopped responding for some reason.

(c) New device probe requests keeps coming in before existing device
probe requests complete.

The phenomenon syzbot is reporting is (b). A process which is holding
system_transition_mutex and misc_mtx is waiting for probe_count to become
0 inside wait_for_device_probe(), but the probe function which is called
from hub_event() work function is waiting for the processes which are
blocked at mutex_lock(&misc_mtx) to respond via /dev/raw-gadget interface.

This patch mitigates (b) by deferring wait_for_device_probe() from
snapshot_open() to snapshot_write() and snapshot_ioctl(). Please note that
the possibility of (b) remains as long as any thread which is emulating a
USB device via /dev/raw-gadget interface can be blocked by uninterruptible
blocking operations (e.g. mutex_lock()).

Please also note that (a) and (c) are not addressed. Regarding (c), we
should change the code to wait for only one device which contains the
image for resuming from hibernation. I don't know how to address (a), for
use of timeout for wait_for_device_probe() might result in loss of user
data in the image. Maybe we should require the userland to wait for the
image device before opening /dev/snapshot interface.

Link: https://syzkaller.appspot.com/bug?extid=358c9ab4c93da7b7238c [1]
Reported-by: syzbot <[email protected]>
Signed-off-by: Tetsuo Handa <[email protected]>
Tested-by: syzbot <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

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PM: hibernate: Fix snapshot partial write lengths

snapshot_write() is inappropriately limiting the amount of data that can
be written in cases where a partial page has already been written. For
exam

PM: hibernate: Fix snapshot partial write lengths

snapshot_write() is inappropriately limiting the amount of data that can
be written in cases where a partial page has already been written. For
example, one would expect to be able to write 1 byte, then 4095 bytes to
the snapshot device, and have both of those complete fully (since now
we're aligned to a page again). But what ends up happening is we write 1
byte, then 4094/4095 bytes complete successfully.

The reason is that simple_write_to_buffer()'s second argument is the
total size of the buffer, not the size of the buffer minus the offset.
Since simple_write_to_buffer() accounts for the offset in its
implementation, snapshot_write() can just pass the full page size
directly down.

Signed-off-by: Evan Green <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

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mm: split swap_type_of

swap_type_of is used for two entirely different purposes:

(1) check what swap type a given device/offset corresponds to
(2) find the first available swap device that can be

mm: split swap_type_of

swap_type_of is used for two entirely different purposes:

(1) check what swap type a given device/offset corresponds to
(2) find the first available swap device that can be written to

Mixing both in a single function creates an unreadable mess. Create two
separate functions instead, and switch both to pass a dev_t instead of
a struct block_device to further simplify the code.

Signed-off-by: Christoph Hellwig <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>

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PM: rewrite is_hibernate_resume_dev to not require an inode

Just check the dev_t to help simplifying the code.

Signed-off-by: Christoph Hellwig <[email protected]>
Acked-by: Rafael J. Wysocki <rafael.j.wy

PM: rewrite is_hibernate_resume_dev to not require an inode

Just check the dev_t to help simplifying the code.

Signed-off-by: Christoph Hellwig <[email protected]>
Acked-by: Rafael J. Wysocki <[email protected]>
Acked-by: Pavel Machek <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>

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notifier: Fix broken error handling pattern

The current notifiers have the following error handling pattern all
over the place:

int err, nr;

err = __foo_notifier_call_chain(&chain, val_up, v, -1

notifier: Fix broken error handling pattern

The current notifiers have the following error handling pattern all
over the place:

int err, nr;

err = __foo_notifier_call_chain(&chain, val_up, v, -1, &nr);
if (err & NOTIFIER_STOP_MASK)
__foo_notifier_call_chain(&chain, val_down, v, nr-1, NULL)

And aside from the endless repetition thereof, it is broken. Consider
blocking notifiers; both calls take and drop the rwsem, this means
that the notifier list can change in between the two calls, making @nr
meaningless.

Fix this by replacing all the __foo_notifier_call_chain() functions
with foo_notifier_call_chain_robust() that embeds the above pattern,
but ensures it is inside a single lock region.

Note: I switched atomic_notifier_call_chain_robust() to use
the spinlock, since RCU cannot provide the guarantee
required for the recovery.

Note: software_resume() error handling was broken afaict.

Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Acked-by: Rafael J. Wysocki <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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PM: hibernate: Restrict writes to the resume device

Hibernation via snapshot device requires write permission to the swap
block device, the one that more often (but not necessarily) is used to
store

PM: hibernate: Restrict writes to the resume device

Hibernation via snapshot device requires write permission to the swap
block device, the one that more often (but not necessarily) is used to
store the hibernation image.

With this patch, such permissions are granted iff:

1) snapshot device config option is enabled
2) swap partition is used as resume device

In other circumstances the swap device is not writable from userspace.

In order to achieve this, every write attempt to a swap device is
checked against the device configured as part of the uswsusp API [0]
using a pointer to the inode struct in memory. If the swap device being
written was not configured for resuming, the write request is denied.

NOTE: this implementation works only for swap block devices, where the
inode configured by swapon (which sets S_SWAPFILE) is the same used
by SNAPSHOT_SET_SWAP_AREA.

In case of swap file, SNAPSHOT_SET_SWAP_AREA indeed receives the inode
of the block device containing the filesystem where the swap file is
located (+ offset in it) which is never passed to swapon and then has
not set S_SWAPFILE.

As result, the swap file itself (as a file) has never an option to be
written from userspace. Instead it remains writable if accessed directly
from the containing block device, which is always writeable from root.

[0] Documentation/power/userland-swsusp.rst

v2:
- rename is_hibernate_snapshot_dev() to is_hibernate_resume_dev()
- fix description so to correctly refer to the resume device

Signed-off-by: Domenico Andreoli <[email protected]>
Acked-by: Darrick J. Wong <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

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PM: hibernate: Incorporate concurrency handling

Hibernation concurrency handling is currently delegated to user.c,
where it's also used for regulating the access to the snapshot device.

In the pros

PM: hibernate: Incorporate concurrency handling

Hibernation concurrency handling is currently delegated to user.c,
where it's also used for regulating the access to the snapshot device.

In the prospective of making user.c a separate configuration option,
such mutual exclusion is brought into hibernate.c and made available
through accessor helpers hereby introduced.

Signed-off-by: Domenico Andreoli <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

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PM / sleep: handle the compat case in snapshot_set_swap_area()

Use in_compat_syscall to copy directly from the 32-bit ABI structure.

Signed-off-by: Christoph Hellwig <[email protected]>
Signed-off-by: Raf

PM / sleep: handle the compat case in snapshot_set_swap_area()

Use in_compat_syscall to copy directly from the 32-bit ABI structure.

Signed-off-by: Christoph Hellwig <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

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PM / sleep: move SNAPSHOT_SET_SWAP_AREA handling into a helper

Move the handling of the SNAPSHOT_SET_SWAP_AREA ioctl from the main
ioctl helper into a helper function.

Signed-off-by: Christoph Hell

PM / sleep: move SNAPSHOT_SET_SWAP_AREA handling into a helper

Move the handling of the SNAPSHOT_SET_SWAP_AREA ioctl from the main
ioctl helper into a helper function.

Signed-off-by: Christoph Hellwig <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

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misc: cleanup minor number definitions in c file into miscdevice.h

HWRNG_MINOR and RNG_MISCDEV_MINOR are duplicate definitions, use
unified HWRNG_MINOR instead and moved into miscdevice.h

ANSLCD_MI

misc: cleanup minor number definitions in c file into miscdevice.h

HWRNG_MINOR and RNG_MISCDEV_MINOR are duplicate definitions, use
unified HWRNG_MINOR instead and moved into miscdevice.h

ANSLCD_MINOR and LCD_MINOR are duplicate definitions, use unified
LCD_MINOR instead and moved into miscdevice.h

MISCDEV_MINOR is renamed to PXA3XX_GCU_MINOR and moved into
miscdevice.h

Other definitions are just moved without any change.

Link: https://lore.kernel.org/lkml/[email protected]/t/
Suggested-by: Arnd Bergmann <[email protected]>
Build-tested-by: Willy TARREAU <[email protected]>
Build-tested-by: Miguel Ojeda <[email protected]>
Signed-off-by: Zhenzhong Duan <[email protected]>
Acked-by: Miguel Ojeda <[email protected]>
Acked-by: Arnd Bergmann <[email protected]>
Acked-by: Herbert Xu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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PM / hibernate: Remove unnecessary compat ioctl overrides

Since the SNAPSHOT_GET_IMAGE_SIZE, SNAPSHOT_AVAIL_SWAP_SIZE, and
SNAPSHOT_ALLOC_SWAP_PAGE ioctls produce an loff_t result, and loff_t is
alw

PM / hibernate: Remove unnecessary compat ioctl overrides

Since the SNAPSHOT_GET_IMAGE_SIZE, SNAPSHOT_AVAIL_SWAP_SIZE, and
SNAPSHOT_ALLOC_SWAP_PAGE ioctls produce an loff_t result, and loff_t is
always 64-bit even in the compat case, there's no reason to have the
special compat handling for these ioctls. Just remove this unneeded
code so that these ioctls call into snapshot_ioctl() directly, doing
just the compat_ptr() conversion on the argument.

(This unnecessary code was also causing a KMSAN false positive.)

Signed-off-by: Eric Biggers <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428

Based on 1 normalized pattern(s):

this file is released under the gplv2

extracted by the scancode license scanner the SPDX lice

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428

Based on 1 normalized pattern(s):

this file is released under the gplv2

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 68 file(s).

Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Armijn Hemel <[email protected]>
Reviewed-by: Allison Randal <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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PM / sleep: Refactor filesystems sync to reduce duplication

Create a common helper to sync filesystems for system suspend and
hibernation.

Signed-off-by: Harry Pan <[email protected]>
Acked-by: P

PM / sleep: Refactor filesystems sync to reduce duplication

Create a common helper to sync filesystems for system suspend and
hibernation.

Signed-off-by: Harry Pan <[email protected]>
Acked-by: Pavel Machek <[email protected]>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <[email protected]>

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PM / reboot: Eliminate race between reboot and suspend

At present, "systemctl suspend" and "shutdown" can run in parrallel. A
system can suspend after devices_shutdown(), and resume. Then the shutdo

PM / reboot: Eliminate race between reboot and suspend

At present, "systemctl suspend" and "shutdown" can run in parrallel. A
system can suspend after devices_shutdown(), and resume. Then the shutdown
task goes on to power off. This causes many devices are not really shut
off. Hence replacing reboot_mutex with system_transition_mutex (renamed
from pm_mutex) to achieve the exclusion. The renaming of pm_mutex as
system_transition_mutex can be better to reflect the purpose of the mutex.

Signed-off-by: Pingfan Liu <[email protected]>
Acked-by: Pavel Machek <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

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PM / hibernate: Fix oops at snapshot_write()

syzbot is reporting NULL pointer dereference at snapshot_write() [1].
This is because data->handle is zero-cleared by ioctl(SNAPSHOT_FREE).
Fix this by c

PM / hibernate: Fix oops at snapshot_write()

syzbot is reporting NULL pointer dereference at snapshot_write() [1].
This is because data->handle is zero-cleared by ioctl(SNAPSHOT_FREE).
Fix this by checking data_of(data->handle) != NULL before using it.

[1] https://syzkaller.appspot.com/bug?id=828a3c71bd344a6de8b6a31233d51a72099f27fd

Signed-off-by: Tetsuo Handa <[email protected]>
Reported-by: syzbot <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

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fs: add ksys_sync() helper; remove in-kernel calls to sys_sync()

Using this helper allows us to avoid the in-kernel calls to the
sys_sync() syscall. The ksys_ prefix denotes that this function
is me

fs: add ksys_sync() helper; remove in-kernel calls to sys_sync()

Using this helper allows us to avoid the in-kernel calls to the
sys_sync() syscall. The ksys_ prefix denotes that this function
is meant as a drop-in replacement for the syscall. In particular, it
uses the same calling convention as sys_sync().

This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/[email protected]

Cc: Alexander Viro <[email protected]>
Signed-off-by: Dominik Brodowski <[email protected]>

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Replace <asm/uaccess.h> with <linux/uaccess.h> globally

This was entirely automated, using the script by Al:

PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PA

Replace <asm/uaccess.h> with <linux/uaccess.h> globally

This was entirely automated, using the script by Al:

PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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PM / sleep: make PM notifiers called symmetrically

This makes pm notifier PREPARE/POST symmetrical: if PREPARE
fails, we will only undo what ever happened on PREPARE.

It fixes the unbalanced CPU ho

PM / sleep: make PM notifiers called symmetrically

This makes pm notifier PREPARE/POST symmetrical: if PREPARE
fails, we will only undo what ever happened on PREPARE.

It fixes the unbalanced CPU hotplug enable in CPU PM notifier.

Signed-off-by: Lianwei Wang <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

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PM / hibernate: introduce "nohibernate" boot parameter

To support using kernel features that are not compatible with hibernation,
this creates the "nohibernate" kernel boot parameter to disable both

PM / hibernate: introduce "nohibernate" boot parameter

To support using kernel features that are not compatible with hibernation,
this creates the "nohibernate" kernel boot parameter to disable both
hibernation and resume. This allows hibernation support to be a boot-time
choice instead of only a compile-time choice.

Signed-off-by: Kees Cook <[email protected]>
Acked-by: Pavel Machek <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

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PM / Hibernate: Do not crash kernel in free_basic_memory_bitmaps()

I have received a report about the BUG_ON() in free_basic_memory_bitmaps()
triggering mysteriously during an aborted s2disk hiberna

PM / Hibernate: Do not crash kernel in free_basic_memory_bitmaps()

I have received a report about the BUG_ON() in free_basic_memory_bitmaps()
triggering mysteriously during an aborted s2disk hibernation attempt.
The only way I can explain that is that /dev/snapshot was first
opened for writing (resume mode), then closed and then opened again
for reading and closed again without freezing tasks. In that case
the first invocation of snapshot_open() would set the free_bitmaps
flag in snapshot_state, which is a static variable. That flag
wouldn't be cleared later and the second invocation of snapshot_open()
would just leave it like that, so the subsequent snapshot_release()
would see data->frozen set and free_basic_memory_bitmaps() would be
called unnecessarily.

To prevent that from happening clear data->free_bitmaps in
snapshot_open() when the file is being opened for reading (hibernate
mode).

In addition to that, replace the BUG_ON() in free_basic_memory_bitmaps()
with a WARN_ON() as the kernel can continue just fine if the condition
checked by that macro occurs.

Fixes: aab172891542 (PM / hibernate: Fix user space driven resume regression)
Reported-by: Oliver Lorenz <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>
Cc: 3.12+ <[email protected]> # 3.12+

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PM / Hibernate: Use bool for boolean fields of struct snapshot_data

The snapshot_data structure used internally by the hibernate user
space interface code in user.c has three char fields that are us

PM / Hibernate: Use bool for boolean fields of struct snapshot_data

The snapshot_data structure used internally by the hibernate user
space interface code in user.c has three char fields that are used
to store boolean values. Change their data type to bool and use
true and false instead of 1 and 0, respectively, in assignments
involving those fields.

Signed-off-by: Rafael J. Wysocki <[email protected]>

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PM / hibernate: Fix user space driven resume regression

Recent commit 8fd37a4 (PM / hibernate: Create memory bitmaps after
freezing user space) broke the resume part of the user space driven
hiberna

PM / hibernate: Fix user space driven resume regression

Recent commit 8fd37a4 (PM / hibernate: Create memory bitmaps after
freezing user space) broke the resume part of the user space driven
hibernation (s2disk), because I forgot that the resume utility
loaded the image into memory without freezing user space (it still
freezes tasks after loading the image). This means that during user
space driven resume we need to create the memory bitmaps at the
"device open" time rather than at the "freeze tasks" time, so make
that happen (that's a special case anyway, so it needs to be treated
in a special way).

Reported-and-tested-by: Ronald <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

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