Searched +hist:67 +hist:be2dd1 (Results 1 - 19 of 19) sorted by relevance

/linux-master/drivers/pci/
H A Drom.cdiff 4cc59c72 Mon Feb 09 10:31:20 MST 2009 Randy Dunlap <randy.dunlap@oracle.com> PCI: fix rom.c kernel-doc warning

Fix PCI kernel-doc warning:

Warning(linux-2.6.29-rc4-git1/drivers/pci/rom.c:67): No description found for parameter 'pdev'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
/linux-master/drivers/pnp/
H A Dmanager.cdiff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
/linux-master/fs/
H A Dseq_file.cdiff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
H A Dmpage.cdiff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
H A Dbuffer.cdiff 67f2519f Tue Oct 24 11:21:48 MDT 2017 Greg Edwards <gedwards@ddn.com> fs: guard_bio_eod() needs to consider partitions

guard_bio_eod() needs to look at the partition capacity, not just the
capacity of the whole device, when determining if truncation is
necessary.

[ 60.268688] attempt to access beyond end of device
[ 60.268690] unknown-block(9,1): rw=0, want=67103509, limit=67103506
[ 60.268693] buffer_io_error: 2 callbacks suppressed
[ 60.268696] Buffer I/O error on dev md1p7, logical block 4524305, async page read

Fixes: 74d46992e0d9 ("block: replace bi_bdev with a gendisk pointer and partitions index")
Cc: stable@vger.kernel.org # v4.13
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Edwards <gedwards@ddn.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff 5b41e74a Fri Mar 28 15:15:52 MDT 2008 Dmitri Monakhov <dmonakhov@openvz.org> vfs: fix data leak in nobh_write_end()

Current nobh_write_end() implementation ignore partial writes(copied < len)
case if page was fully mapped and simply mark page as Uptodate, which is
totally wrong because area [pos+copied, pos+len) wasn't updated explicitly in
previous write_begin call. It simply contains garbage from pagecache and
result in data leakage.

#TEST_CASE_BEGIN:
~~~~~~~~~~~~~~~~
In fact issue triggered by classical testcase
open("/mnt/test", O_RDWR|O_CREAT|O_TRUNC, 0666) = 3
ftruncate(3, 409600) = 0
writev(3, [{"a", 1}, {NULL, 4095}], 2) = 1
##TESTCASE_SOURCE:
~~~~~~~~~~~~~~~~~
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <sys/uio.h>
#include <sys/mman.h>
#include <errno.h>
int main(int argc, char **argv)
{
int fd, ret;
void* p;
struct iovec iov[2];
fd = open(argv[1], O_RDWR|O_CREAT|O_TRUNC, 0666);
ftruncate(fd, 409600);
iov[0].iov_base="a";
iov[0].iov_len=1;
iov[1].iov_base=NULL;
iov[1].iov_len=4096;
ret = writev(fd, iov, sizeof(iov)/sizeof(struct iovec));
printf("writev = %d, err = %d\n", ret, errno);
return 0;
}
##TESTCASE RESULT:
~~~~~~~~~~~~~~~~~~
[root@ts63 ~]# mount | grep mnt2
/dev/mapper/test on /mnt2 type ext2 (rw,nobh)
[root@ts63 ~]# /tmp/writev /mnt2/test
writev = 1, err = 0
[root@ts63 ~]# hexdump -C /mnt2/test

00000000 61 65 62 6f 6f 74 00 00 f0 b9 b4 59 3a 00 00 00 |aeboot.....Y:...|
00000010 20 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00 | .......!.......|
00000020 df df df df df df df df df df df df df df df df |................|
00000030 3a 00 00 00 2a 00 00 00 21 00 00 00 00 00 00 00 |:...*...!.......|
00000040 60 c0 8c 00 00 00 00 00 40 4a 8d 00 00 00 00 00 |`.......@J......|
00000050 00 00 00 00 00 00 00 00 41 00 00 00 00 00 00 00 |........A.......|
00000060 74 69 6d 65 20 64 64 20 69 66 3d 2f 64 65 76 2f |time dd if=/dev/|
00000070 6c 6f 6f 70 30 20 20 6f 66 3d 2f 64 65 76 2f 6e |loop0 of=/dev/n|
skip..
00000f50 00 00 00 00 00 00 00 00 31 00 00 00 00 00 00 00 |........1.......|
00000f60 6d 6b 66 73 2e 65 78 74 33 20 2f 64 65 76 2f 76 |mkfs.ext3 /dev/v|
00000f70 7a 76 67 2f 74 65 73 74 20 2d 62 34 30 39 36 00 |zvg/test -b4096.|
00000f80 a0 fe 8c 00 00 00 00 00 21 00 00 00 00 00 00 00 |........!.......|
00000f90 23 31 32 30 35 39 35 30 34 30 34 00 3a 00 00 00 |#1205950404.:...|
00000fa0 20 00 8d 00 00 00 00 00 21 00 00 00 00 00 00 00 | .......!.......|
00000fb0 d0 cf 8c 00 00 00 00 00 10 d0 8c 00 00 00 00 00 |................|
00000fc0 00 00 00 00 00 00 00 00 41 00 00 00 00 00 00 00 |........A.......|
00000fd0 6d 6f 75 6e 74 20 2f 64 65 76 2f 76 7a 76 67 2f |mount /dev/vzvg/|
00000fe0 74 65 73 74 20 20 2f 76 7a 20 2d 6f 20 64 61 74 |test /vz -o dat|
00000ff0 61 3d 77 72 69 74 65 62 61 63 6b 00 00 00 00 00 |a=writeback.....|
00001000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|

As you can see file's page contains garbage from pagecache instead of zeros.
#TEST_CASE_END

Attached patch:
- Add sanity check BUG_ON in order to prevent incorrect usage by caller,
This is function invariant because page can has buffers and in no zero
*fadata pointer at the same time.
- Always attach buffers to page is it is partial write case.
- Always switch back to generic_write_end if page has buffers.
This is reasonable because if page already has buffer then generic_write_begin
was called previously.

Signed-off-by: Dmitri Monakhov <dmonakhov@openvz.org>
Reviewed-by: Nick Piggin <npiggin@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff 5b41e74a Fri Mar 28 15:15:52 MDT 2008 Dmitri Monakhov <dmonakhov@openvz.org> vfs: fix data leak in nobh_write_end()

Current nobh_write_end() implementation ignore partial writes(copied < len)
case if page was fully mapped and simply mark page as Uptodate, which is
totally wrong because area [pos+copied, pos+len) wasn't updated explicitly in
previous write_begin call. It simply contains garbage from pagecache and
result in data leakage.

#TEST_CASE_BEGIN:
~~~~~~~~~~~~~~~~
In fact issue triggered by classical testcase
open("/mnt/test", O_RDWR|O_CREAT|O_TRUNC, 0666) = 3
ftruncate(3, 409600) = 0
writev(3, [{"a", 1}, {NULL, 4095}], 2) = 1
##TESTCASE_SOURCE:
~~~~~~~~~~~~~~~~~
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <sys/uio.h>
#include <sys/mman.h>
#include <errno.h>
int main(int argc, char **argv)
{
int fd, ret;
void* p;
struct iovec iov[2];
fd = open(argv[1], O_RDWR|O_CREAT|O_TRUNC, 0666);
ftruncate(fd, 409600);
iov[0].iov_base="a";
iov[0].iov_len=1;
iov[1].iov_base=NULL;
iov[1].iov_len=4096;
ret = writev(fd, iov, sizeof(iov)/sizeof(struct iovec));
printf("writev = %d, err = %d\n", ret, errno);
return 0;
}
##TESTCASE RESULT:
~~~~~~~~~~~~~~~~~~
[root@ts63 ~]# mount | grep mnt2
/dev/mapper/test on /mnt2 type ext2 (rw,nobh)
[root@ts63 ~]# /tmp/writev /mnt2/test
writev = 1, err = 0
[root@ts63 ~]# hexdump -C /mnt2/test

00000000 61 65 62 6f 6f 74 00 00 f0 b9 b4 59 3a 00 00 00 |aeboot.....Y:...|
00000010 20 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00 | .......!.......|
00000020 df df df df df df df df df df df df df df df df |................|
00000030 3a 00 00 00 2a 00 00 00 21 00 00 00 00 00 00 00 |:...*...!.......|
00000040 60 c0 8c 00 00 00 00 00 40 4a 8d 00 00 00 00 00 |`.......@J......|
00000050 00 00 00 00 00 00 00 00 41 00 00 00 00 00 00 00 |........A.......|
00000060 74 69 6d 65 20 64 64 20 69 66 3d 2f 64 65 76 2f |time dd if=/dev/|
00000070 6c 6f 6f 70 30 20 20 6f 66 3d 2f 64 65 76 2f 6e |loop0 of=/dev/n|
skip..
00000f50 00 00 00 00 00 00 00 00 31 00 00 00 00 00 00 00 |........1.......|
00000f60 6d 6b 66 73 2e 65 78 74 33 20 2f 64 65 76 2f 76 |mkfs.ext3 /dev/v|
00000f70 7a 76 67 2f 74 65 73 74 20 2d 62 34 30 39 36 00 |zvg/test -b4096.|
00000f80 a0 fe 8c 00 00 00 00 00 21 00 00 00 00 00 00 00 |........!.......|
00000f90 23 31 32 30 35 39 35 30 34 30 34 00 3a 00 00 00 |#1205950404.:...|
00000fa0 20 00 8d 00 00 00 00 00 21 00 00 00 00 00 00 00 | .......!.......|
00000fb0 d0 cf 8c 00 00 00 00 00 10 d0 8c 00 00 00 00 00 |................|
00000fc0 00 00 00 00 00 00 00 00 41 00 00 00 00 00 00 00 |........A.......|
00000fd0 6d 6f 75 6e 74 20 2f 64 65 76 2f 76 7a 76 67 2f |mount /dev/vzvg/|
00000fe0 74 65 73 74 20 20 2f 76 7a 20 2d 6f 20 64 61 74 |test /vz -o dat|
00000ff0 61 3d 77 72 69 74 65 62 61 63 6b 00 00 00 00 00 |a=writeback.....|
00001000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|

As you can see file's page contains garbage from pagecache instead of zeros.
#TEST_CASE_END

Attached patch:
- Add sanity check BUG_ON in order to prevent incorrect usage by caller,
This is function invariant because page can has buffers and in no zero
*fadata pointer at the same time.
- Always attach buffers to page is it is partial write case.
- Always switch back to generic_write_end if page has buffers.
This is reasonable because if page already has buffer then generic_write_begin
was called previously.

Signed-off-by: Dmitri Monakhov <dmonakhov@openvz.org>
Reviewed-by: Nick Piggin <npiggin@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
H A Dfs-writeback.cdiff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
/linux-master/net/core/
H A Ddatagram.cdiff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
/linux-master/lib/
H A Dkobject.cdiff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
/linux-master/drivers/base/
H A Dplatform.cdiff 67e532a4 Wed Dec 22 03:42:13 MST 2021 Johan Hovold <johan@kernel.org> driver core: platform: document registration-failure requirement

Add an explicit comment to document that the reference initialised by
platform_device_register() needs to be released by a call to
platform_device_put() also when registration fails (cf.
device_register()).

Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211222104213.5673-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 112d125a Mon Feb 15 01:52:59 MST 2016 Greg Kroah-Hartman <gregkh@linuxfoundation.org> Revert "driver-core: platform: probe of-devices only using list of compatibles"

This reverts commit 67d02a1bbb334558e9380409a3cd426b36d4578b

This should reallow binding of of-devices by name.

It turned out that there are valid reasons (e.g. step by step conversion
to device tree probing using auxdata) to bind of-instantiated devices to
drivers by name. So revert to the original logic.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Thierry Reding <treding@nvidia.com>
Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
diff 67d02a1b Fri Nov 13 01:14:20 MST 2015 Uwe Kleine-König <u.kleine-koenig@pengutronix.de> driver-core: platform: probe of-devices only using list of compatibles

There are several indications that make a platform device match a
platform driver. For devices that are instantiated by a device tree
matching by name, id table or acpi mechanisms doesn't make sense and
might result in surprising effects. So limit matching to use the
driver's of_match_table for these.

Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 00d3dcdd Wed Nov 09 10:23:39 MST 2005 Russell King <rmk@dyn-67.arm.linux.org.uk> [DRIVER MODEL] Add platform_driver

Introduce struct platform_driver. This allows the platform device
driver methods to be passed a platform_device structure instead of
instead of a plain device structure, and therefore requiring casting
in every platform driver.

We introduce this in such a way that any existing platform drivers
registered directly via driver_register continue to work as before,
thereby allowing a gradual conversion to the new platform_driver
methods.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
diff 37c12e74 Sat Nov 05 14:19:33 MST 2005 Russell King <rmk@dyn-67.arm.linux.org.uk> [DRIVER MODEL] Improved dynamically allocated platform_device interface

Re-jig the simple platform device support to allow private data
to be attached to a platform device, as well as allowing the
parent device to be set.

Example usage:

pdev = platform_device_alloc("mydev", id);
if (pdev) {
err = platform_device_add_resources(pdev, &resources,
ARRAY_SIZE(resources));
if (err == 0)
err = platform_device_add_data(pdev, &platform_data,
sizeof(platform_data));
if (err == 0)
err = platform_device_add(pdev);
} else {
err = -ENOMEM;
}
if (err)
platform_device_put(pdev);

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
diff d052d1be Sat Oct 29 12:07:23 MDT 2005 Russell King <rmk@dyn-67.arm.linux.org.uk> Create platform_device.h to contain all the platform device details.
Convert everyone who uses platform_bus_type to include
linux/platform_device.h.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
/linux-master/fs/sysfs/
H A Dfile.cdiff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
/linux-master/mm/
H A Dtruncate.cdiff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
H A Dpage-writeback.cdiff 67fd707f Wed Nov 15 18:35:19 MST 2017 Jan Kara <jack@suse.cz> mm: remove nr_pages argument from pagevec_lookup_{,range}_tag()

All users of pagevec_lookup() and pagevec_lookup_range() now pass
PAGEVEC_SIZE as a desired number of pages. Just drop the argument.

Link: http://lkml.kernel.org/r/20171009151359.31984-15-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff 143dfe86 Fri Aug 27 18:45:12 MDT 2010 Wu Fengguang <fengguang.wu@intel.com> writeback: IO-less balance_dirty_pages()

As proposed by Chris, Dave and Jan, don't start foreground writeback IO
inside balance_dirty_pages(). Instead, simply let it idle sleep for some
time to throttle the dirtying task. In the mean while, kick off the
per-bdi flusher thread to do background writeback IO.

RATIONALS
=========

- disk seeks on concurrent writeback of multiple inodes (Dave Chinner)

If every thread doing writes and being throttled start foreground
writeback, it leads to N IO submitters from at least N different
inodes at the same time, end up with N different sets of IO being
issued with potentially zero locality to each other, resulting in
much lower elevator sort/merge efficiency and hence we seek the disk
all over the place to service the different sets of IO.
OTOH, if there is only one submission thread, it doesn't jump between
inodes in the same way when congestion clears - it keeps writing to
the same inode, resulting in large related chunks of sequential IOs
being issued to the disk. This is more efficient than the above
foreground writeback because the elevator works better and the disk
seeks less.

- lock contention and cache bouncing on concurrent IO submitters (Dave Chinner)

With this patchset, the fs_mark benchmark on a 12-drive software RAID0 goes
from CPU bound to IO bound, freeing "3-4 CPUs worth of spinlock contention".

* "CPU usage has dropped by ~55%", "it certainly appears that most of
the CPU time saving comes from the removal of contention on the
inode_wb_list_lock" (IMHO at least 10% comes from the reduction of
cacheline bouncing, because the new code is able to call much less
frequently into balance_dirty_pages() and hence access the global
page states)

* the user space "App overhead" is reduced by 20%, by avoiding the
cacheline pollution by the complex writeback code path

* "for a ~5% throughput reduction", "the number of write IOs have
dropped by ~25%", and the elapsed time reduced from 41:42.17 to
40:53.23.

* On a simple test of 100 dd, it reduces the CPU %system time from 30% to 3%,
and improves IO throughput from 38MB/s to 42MB/s.

- IO size too small for fast arrays and too large for slow USB sticks

The write_chunk used by current balance_dirty_pages() cannot be
directly set to some large value (eg. 128MB) for better IO efficiency.
Because it could lead to more than 1 second user perceivable stalls.
Even the current 4MB write size may be too large for slow USB sticks.
The fact that balance_dirty_pages() starts IO on itself couples the
IO size to wait time, which makes it hard to do suitable IO size while
keeping the wait time under control.

Now it's possible to increase writeback chunk size proportional to the
disk bandwidth. In a simple test of 50 dd's on XFS, 1-HDD, 3GB ram,
the larger writeback size dramatically reduces the seek count to 1/10
(far beyond my expectation) and improves the write throughput by 24%.

- long block time in balance_dirty_pages() hurts desktop responsiveness

Many of us may have the experience: it often takes a couple of seconds
or even long time to stop a heavy writing dd/cp/tar command with
Ctrl-C or "kill -9".

- IO pipeline broken by bumpy write() progress

There are a broad class of "loop {read(buf); write(buf);}" applications
whose read() pipeline will be under-utilized or even come to a stop if
the write()s have long latencies _or_ don't progress in a constant rate.
The current threshold based throttling inherently transfers the large
low level IO completion fluctuations to bumpy application write()s,
and further deteriorates with increasing number of dirtiers and/or bdi's.

For example, when doing 50 dd's + 1 remote rsync to an XFS partition,
the rsync progresses very bumpy in legacy kernel, and throughput is
improved by 67% by this patchset. (plus the larger write chunk size,
it will be 93% speedup).

The new rate based throttling can support 1000+ dd's with excellent
smoothness, low latency and low overheads.

For the above reasons, it's much better to do IO-less and low latency
pauses in balance_dirty_pages().

Jan Kara, Dave Chinner and me explored the scheme to let
balance_dirty_pages() wait for enough writeback IO completions to
safeguard the dirty limit. However it's found to have two problems:

- in large NUMA systems, the per-cpu counters may have big accounting
errors, leading to big throttle wait time and jitters.

- NFS may kill large amount of unstable pages with one single COMMIT.
Because NFS server serves COMMIT with expensive fsync() IOs, it is
desirable to delay and reduce the number of COMMITs. So it's not
likely to optimize away such kind of bursty IO completions, and the
resulted large (and tiny) stall times in IO completion based throttling.

So here is a pause time oriented approach, which tries to control the
pause time in each balance_dirty_pages() invocations, by controlling
the number of pages dirtied before calling balance_dirty_pages(), for
smooth and efficient dirty throttling:

- avoid useless (eg. zero pause time) balance_dirty_pages() calls
- avoid too small pause time (less than 4ms, which burns CPU power)
- avoid too large pause time (more than 200ms, which hurts responsiveness)
- avoid big fluctuations of pause times

It can control pause times at will. The default policy (in a followup
patch) will be to do ~10ms pauses in 1-dd case, and increase to ~100ms
in 1000-dd case.

BEHAVIOR CHANGE
===============

(1) dirty threshold

Users will notice that the applications will get throttled once crossing
the global (background + dirty)/2=15% threshold, and then balanced around
17.5%. Before patch, the behavior is to just throttle it at 20% dirtyable
memory in 1-dd case.

Since the task will be soft throttled earlier than before, it may be
perceived by end users as performance "slow down" if his application
happens to dirty more than 15% dirtyable memory.

(2) smoothness/responsiveness

Users will notice a more responsive system during heavy writeback.
"killall dd" will take effect instantly.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
H A Dfilemap.cdiff 67fd707f Wed Nov 15 18:35:19 MST 2017 Jan Kara <jack@suse.cz> mm: remove nr_pages argument from pagevec_lookup_{,range}_tag()

All users of pagevec_lookup() and pagevec_lookup_range() now pass
PAGEVEC_SIZE as a desired number of pages. Just drop the argument.

Link: http://lkml.kernel.org/r/20171009151359.31984-15-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff 67f9fd91 Thu Apr 03 15:48:18 MDT 2014 Sasha Levin <sasha.levin@oracle.com> mm: remove read_cache_page_async()

This patch removes read_cache_page_async() which wasn't really needed
anywhere and simplifies the code around it a bit.

read_cache_page_async() is useful when we want to read a page into the
cache without waiting for it to complete. This happens when the
appropriate callback 'filler' doesn't complete its read operation and
releases the page lock immediately, and instead queues a different
completion routine to do that. This never actually happened anywhere in
the code.

read_cache_page_async() had 3 different callers:

- read_cache_page() which is the sync version, it would just wait for
the requested read to complete using wait_on_page_read().

- JFFS2 would call it from jffs2_gc_fetch_page(), but the filler
function it supplied doesn't do any async reads, and would complete
before the filler function returns - making it actually a sync read.

- CRAMFS would call it using the read_mapping_page_async() wrapper, with
a similar story to JFFS2 - the filler function doesn't do anything that
reminds async reads and would always complete before the filler function
returns.

To sum it up, the code in mm/filemap.c never took advantage of having
read_cache_page_async(). While there are filler callbacks that do async
reads (such as the block one), we always called it with the
read_cache_page().

This patch adds a mandatory wait for read to complete when adding a new
page to the cache, and removes read_cache_page_async() and its wrappers.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff 67d58ac4 Tue Jan 06 15:40:28 MST 2009 Nick Piggin <npiggin@suse.de> mm: pagecache gfp flags fix

Frustratingly, gfp_t is really divided into two classes of flags. One are
the context dependent ones (can we sleep? can we enter filesystem? block
subsystem? should we use some extra reserves, etc.). The other ones are
the type of memory required and depend on how the algorithm is implemented
rather than the point at which the memory is allocated (highmem? dma
memory? etc).

Some of the functions which allocate a page and add it to page cache take
a gfp_t, but sometimes those functions or their callers aren't really
doing the right thing: when allocating pagecache page, the memory type
should be mapping_gfp_mask(mapping). When allocating radix tree nodes,
the memory type should be kernel mapped (not highmem) memory. The gfp_t
argument should only really be needed for context dependent options.

This patch doesn't really solve that tangle in a nice way, but it does
attempt to fix a couple of bugs.

- find_or_create_page changes its radix-tree allocation to only include
the main context dependent flags in order so the pagecache page may be
allocated from arbitrary types of memory without affecting the
radix-tree. In practice, slab allocations don't come from highmem
anyway, and radix-tree only uses slab allocations. So there isn't a
practical change (unless some fs uses GFP_DMA for pages).

- grab_cache_page_nowait() is changed to allocate radix-tree nodes with
GFP_NOFS, because it is not supposed to reenter the filesystem. This
bug could cause lock recursion if a filesystem is not expecting the
function to reenter the fs (as-per documentation).

Filesystems should be careful about exactly what semantics they want and
what they get when fiddling with gfp_t masks to allocate pagecache. One
should be as liberal as possible with the type of memory that can be used,
and same for the the context specific flags.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
/linux-master/drivers/acpi/
H A Dscan.cdiff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
/linux-master/include/net/
H A Dsock.hdiff a37a0ee4 Tue Nov 30 11:29:39 MST 2021 Eric Dumazet <edumazet@google.com> net: avoid uninit-value from tcp_conn_request

A recent change triggers a KMSAN warning, because request
sockets do not initialize @sk_rx_queue_mapping field.

Add sk_rx_queue_update() helper to make our intent clear.

BUG: KMSAN: uninit-value in sk_rx_queue_set include/net/sock.h:1922 [inline]
BUG: KMSAN: uninit-value in tcp_conn_request+0x3bcc/0x4dc0 net/ipv4/tcp_input.c:6922
sk_rx_queue_set include/net/sock.h:1922 [inline]
tcp_conn_request+0x3bcc/0x4dc0 net/ipv4/tcp_input.c:6922
tcp_v4_conn_request+0x218/0x2a0 net/ipv4/tcp_ipv4.c:1528
tcp_rcv_state_process+0x2c5/0x3290 net/ipv4/tcp_input.c:6406
tcp_v4_do_rcv+0xb4e/0x1330 net/ipv4/tcp_ipv4.c:1738
tcp_v4_rcv+0x468d/0x4ed0 net/ipv4/tcp_ipv4.c:2100
ip_protocol_deliver_rcu+0x760/0x10b0 net/ipv4/ip_input.c:204
ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline]
NF_HOOK include/linux/netfilter.h:307 [inline]
ip_local_deliver+0x584/0x8c0 net/ipv4/ip_input.c:252
dst_input include/net/dst.h:460 [inline]
ip_sublist_rcv_finish net/ipv4/ip_input.c:551 [inline]
ip_list_rcv_finish net/ipv4/ip_input.c:601 [inline]
ip_sublist_rcv+0x11fd/0x1520 net/ipv4/ip_input.c:609
ip_list_rcv+0x95f/0x9a0 net/ipv4/ip_input.c:644
__netif_receive_skb_list_ptype net/core/dev.c:5505 [inline]
__netif_receive_skb_list_core+0xe34/0x1240 net/core/dev.c:5553
__netif_receive_skb_list+0x7fc/0x960 net/core/dev.c:5605
netif_receive_skb_list_internal+0x868/0xde0 net/core/dev.c:5696
gro_normal_list net/core/dev.c:5850 [inline]
napi_complete_done+0x579/0xdd0 net/core/dev.c:6587
virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline]
virtnet_poll+0x17b6/0x2350 drivers/net/virtio_net.c:1557
__napi_poll+0x14e/0xbc0 net/core/dev.c:7020
napi_poll net/core/dev.c:7087 [inline]
net_rx_action+0x824/0x1880 net/core/dev.c:7174
__do_softirq+0x1fe/0x7eb kernel/softirq.c:558
invoke_softirq+0xa4/0x130 kernel/softirq.c:432
__irq_exit_rcu kernel/softirq.c:636 [inline]
irq_exit_rcu+0x76/0x130 kernel/softirq.c:648
common_interrupt+0xb6/0xd0 arch/x86/kernel/irq.c:240
asm_common_interrupt+0x1e/0x40
smap_restore arch/x86/include/asm/smap.h:67 [inline]
get_shadow_origin_ptr mm/kmsan/instrumentation.c:31 [inline]
__msan_metadata_ptr_for_load_1+0x28/0x30 mm/kmsan/instrumentation.c:63
tomoyo_check_acl+0x1b0/0x630 security/tomoyo/domain.c:173
tomoyo_path_permission security/tomoyo/file.c:586 [inline]
tomoyo_check_open_permission+0x61f/0xe10 security/tomoyo/file.c:777
tomoyo_file_open+0x24f/0x2d0 security/tomoyo/tomoyo.c:311
security_file_open+0xb1/0x1f0 security/security.c:1635
do_dentry_open+0x4e4/0x1bf0 fs/open.c:809
vfs_open+0xaf/0xe0 fs/open.c:957
do_open fs/namei.c:3426 [inline]
path_openat+0x52f1/0x5dd0 fs/namei.c:3559
do_filp_open+0x306/0x760 fs/namei.c:3586
do_sys_openat2+0x263/0x8f0 fs/open.c:1212
do_sys_open fs/open.c:1228 [inline]
__do_sys_open fs/open.c:1236 [inline]
__se_sys_open fs/open.c:1232 [inline]
__x64_sys_open+0x314/0x380 fs/open.c:1232
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x44/0xae

Uninit was created at:
__alloc_pages+0xbc7/0x10a0 mm/page_alloc.c:5409
alloc_pages+0x8a5/0xb80
alloc_slab_page mm/slub.c:1810 [inline]
allocate_slab+0x287/0x1c20 mm/slub.c:1947
new_slab mm/slub.c:2010 [inline]
___slab_alloc+0xbdf/0x1e90 mm/slub.c:3039
__slab_alloc mm/slub.c:3126 [inline]
slab_alloc_node mm/slub.c:3217 [inline]
slab_alloc mm/slub.c:3259 [inline]
kmem_cache_alloc+0xbb3/0x11c0 mm/slub.c:3264
reqsk_alloc include/net/request_sock.h:91 [inline]
inet_reqsk_alloc+0xaf/0x8b0 net/ipv4/tcp_input.c:6712
tcp_conn_request+0x910/0x4dc0 net/ipv4/tcp_input.c:6852
tcp_v4_conn_request+0x218/0x2a0 net/ipv4/tcp_ipv4.c:1528
tcp_rcv_state_process+0x2c5/0x3290 net/ipv4/tcp_input.c:6406
tcp_v4_do_rcv+0xb4e/0x1330 net/ipv4/tcp_ipv4.c:1738
tcp_v4_rcv+0x468d/0x4ed0 net/ipv4/tcp_ipv4.c:2100
ip_protocol_deliver_rcu+0x760/0x10b0 net/ipv4/ip_input.c:204
ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline]
NF_HOOK include/linux/netfilter.h:307 [inline]
ip_local_deliver+0x584/0x8c0 net/ipv4/ip_input.c:252
dst_input include/net/dst.h:460 [inline]
ip_sublist_rcv_finish net/ipv4/ip_input.c:551 [inline]
ip_list_rcv_finish net/ipv4/ip_input.c:601 [inline]
ip_sublist_rcv+0x11fd/0x1520 net/ipv4/ip_input.c:609
ip_list_rcv+0x95f/0x9a0 net/ipv4/ip_input.c:644
__netif_receive_skb_list_ptype net/core/dev.c:5505 [inline]
__netif_receive_skb_list_core+0xe34/0x1240 net/core/dev.c:5553
__netif_receive_skb_list+0x7fc/0x960 net/core/dev.c:5605
netif_receive_skb_list_internal+0x868/0xde0 net/core/dev.c:5696
gro_normal_list net/core/dev.c:5850 [inline]
napi_complete_done+0x579/0xdd0 net/core/dev.c:6587
virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline]
virtnet_poll+0x17b6/0x2350 drivers/net/virtio_net.c:1557
__napi_poll+0x14e/0xbc0 net/core/dev.c:7020
napi_poll net/core/dev.c:7087 [inline]
net_rx_action+0x824/0x1880 net/core/dev.c:7174
__do_softirq+0x1fe/0x7eb kernel/softirq.c:558

Fixes: 342159ee394d ("net: avoid dirtying sk->sk_rx_queue_mapping")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Link: https://lore.kernel.org/r/20211130182939.2584764-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
diff 8873c064 Tue Oct 02 00:24:26 MDT 2018 Eric Dumazet <edumazet@google.com> tcp: do not release socket ownership in tcp_close()

syzkaller was able to hit the WARN_ON(sock_owned_by_user(sk));
in tcp_close()

While a socket is being closed, it is very possible other
threads find it in rtnetlink dump.

tcp_get_info() will acquire the socket lock for a short amount
of time (slow = lock_sock_fast(sk)/unlock_sock_fast(sk, slow);),
enough to trigger the warning.

Fixes: 67db3e4bfbc9 ("tcp: no longer hold ehash lock while calling tcp_get_info()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff 67cc0d40 Mon Sep 08 17:58:58 MDT 2014 Willem de Bruijn <willemb@google.com> net-timestamp: optimize sock_tx_timestamp default path

Few packets have timestamping enabled. Exit sock_tx_timestamp quickly
in this common case.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
/linux-master/fs/proc/
H A Dbase.cdiff ac311a14 Thu Jul 11 22:00:31 MDT 2019 Shakeel Butt <shakeelb@google.com> oom: decouple mems_allowed from oom_unkillable_task

Commit ef08e3b4981a ("[PATCH] cpusets: confine oom_killer to
mem_exclusive cpuset") introduces a heuristic where a potential
oom-killer victim is skipped if the intersection of the potential victim
and the current (the process triggered the oom) is empty based on the
reason that killing such victim most probably will not help the current
allocating process.

However the commit 7887a3da753e ("[PATCH] oom: cpuset hint") changed the
heuristic to just decrease the oom_badness scores of such potential
victim based on the reason that the cpuset of such processes might have
changed and previously they may have allocated memory on mems where the
current allocating process can allocate from.

Unintentionally 7887a3da753e ("[PATCH] oom: cpuset hint") introduced a
side effect as the oom_badness is also exposed to the user space through
/proc/[pid]/oom_score, so, readers with different cpusets can read
different oom_score of the same process.

Later, commit 6cf86ac6f36b ("oom: filter tasks not sharing the same
cpuset") fixed the side effect introduced by 7887a3da753e by moving the
cpuset intersection back to only oom-killer context and out of
oom_badness. However the combination of ab290adbaf8f ("oom: make
oom_unkillable_task() helper function") and 26ebc984913b ("oom:
/proc/<pid>/oom_score treat kernel thread honestly") unintentionally
brought back the cpuset intersection check into the oom_badness
calculation function.

Other than doing cpuset/mempolicy intersection from oom_badness, the memcg
oom context is also doing cpuset/mempolicy intersection which is quite
wrong and is caught by syzcaller with the following report:

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 28426 Comm: syz-executor.5 Not tainted 5.2.0-rc3-next-20190607
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:__read_once_size include/linux/compiler.h:194 [inline]
RIP: 0010:has_intersects_mems_allowed mm/oom_kill.c:84 [inline]
RIP: 0010:oom_unkillable_task mm/oom_kill.c:168 [inline]
RIP: 0010:oom_unkillable_task+0x180/0x400 mm/oom_kill.c:155
Code: c1 ea 03 80 3c 02 00 0f 85 80 02 00 00 4c 8b a3 10 07 00 00 48 b8 00
00 00 00 00 fc ff df 4d 8d 74 24 10 4c 89 f2 48 c1 ea 03 <80> 3c 02 00 0f
85 67 02 00 00 49 8b 44 24 10 4c 8d a0 68 fa ff ff
RSP: 0018:ffff888000127490 EFLAGS: 00010a03
RAX: dffffc0000000000 RBX: ffff8880a4cd5438 RCX: ffffffff818dae9c
RDX: 100000000c3cc602 RSI: ffffffff818dac8d RDI: 0000000000000001
RBP: ffff8880001274d0 R08: ffff888000086180 R09: ffffed1015d26be0
R10: ffffed1015d26bdf R11: ffff8880ae935efb R12: 8000000061e63007
R13: 0000000000000000 R14: 8000000061e63017 R15: 1ffff11000024ea6
FS: 00005555561f5940(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000607304 CR3: 000000009237e000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
oom_evaluate_task+0x49/0x520 mm/oom_kill.c:321
mem_cgroup_scan_tasks+0xcc/0x180 mm/memcontrol.c:1169
select_bad_process mm/oom_kill.c:374 [inline]
out_of_memory mm/oom_kill.c:1088 [inline]
out_of_memory+0x6b2/0x1280 mm/oom_kill.c:1035
mem_cgroup_out_of_memory+0x1ca/0x230 mm/memcontrol.c:1573
mem_cgroup_oom mm/memcontrol.c:1905 [inline]
try_charge+0xfbe/0x1480 mm/memcontrol.c:2468
mem_cgroup_try_charge+0x24d/0x5e0 mm/memcontrol.c:6073
mem_cgroup_try_charge_delay+0x1f/0xa0 mm/memcontrol.c:6088
do_huge_pmd_wp_page_fallback+0x24f/0x1680 mm/huge_memory.c:1201
do_huge_pmd_wp_page+0x7fc/0x2160 mm/huge_memory.c:1359
wp_huge_pmd mm/memory.c:3793 [inline]
__handle_mm_fault+0x164c/0x3eb0 mm/memory.c:4006
handle_mm_fault+0x3b7/0xa90 mm/memory.c:4053
do_user_addr_fault arch/x86/mm/fault.c:1455 [inline]
__do_page_fault+0x5ef/0xda0 arch/x86/mm/fault.c:1521
do_page_fault+0x71/0x57d arch/x86/mm/fault.c:1552
page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1156
RIP: 0033:0x400590
Code: 06 e9 49 01 00 00 48 8b 44 24 10 48 0b 44 24 28 75 1f 48 8b 14 24 48
8b 7c 24 20 be 04 00 00 00 e8 f5 56 00 00 48 8b 74 24 08 <89> 06 e9 1e 01
00 00 48 8b 44 24 08 48 8b 14 24 be 04 00 00 00 8b
RSP: 002b:00007fff7bc49780 EFLAGS: 00010206
RAX: 0000000000000001 RBX: 0000000000760000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 000000002000cffc RDI: 0000000000000001
RBP: fffffffffffffffe R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000760008
R13: 00000000004c55f2 R14: 0000000000000000 R15: 00007fff7bc499b0
Modules linked in:
---[ end trace a65689219582ffff ]---
RIP: 0010:__read_once_size include/linux/compiler.h:194 [inline]
RIP: 0010:has_intersects_mems_allowed mm/oom_kill.c:84 [inline]
RIP: 0010:oom_unkillable_task mm/oom_kill.c:168 [inline]
RIP: 0010:oom_unkillable_task+0x180/0x400 mm/oom_kill.c:155
Code: c1 ea 03 80 3c 02 00 0f 85 80 02 00 00 4c 8b a3 10 07 00 00 48 b8 00
00 00 00 00 fc ff df 4d 8d 74 24 10 4c 89 f2 48 c1 ea 03 <80> 3c 02 00 0f
85 67 02 00 00 49 8b 44 24 10 4c 8d a0 68 fa ff ff
RSP: 0018:ffff888000127490 EFLAGS: 00010a03
RAX: dffffc0000000000 RBX: ffff8880a4cd5438 RCX: ffffffff818dae9c
RDX: 100000000c3cc602 RSI: ffffffff818dac8d RDI: 0000000000000001
RBP: ffff8880001274d0 R08: ffff888000086180 R09: ffffed1015d26be0
R10: ffffed1015d26bdf R11: ffff8880ae935efb R12: 8000000061e63007
R13: 0000000000000000 R14: 8000000061e63017 R15: 1ffff11000024ea6
FS: 00005555561f5940(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f823000 CR3: 000000009237e000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600

The fix is to decouple the cpuset/mempolicy intersection check from
oom_unkillable_task() and make sure cpuset/mempolicy intersection check is
only done in the global oom context.

[shakeelb@google.com: change function name and update comment]
Link: http://lkml.kernel.org/r/20190628152421.198994-3-shakeelb@google.com
Link: http://lkml.kernel.org/r/20190624212631.87212-3-shakeelb@google.com
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Reported-by: syzbot+d0fc9d3c166bc5e4a94b@syzkaller.appspotmail.com
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Paul Jackson <pj@sgi.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff ac311a14 Thu Jul 11 22:00:31 MDT 2019 Shakeel Butt <shakeelb@google.com> oom: decouple mems_allowed from oom_unkillable_task

Commit ef08e3b4981a ("[PATCH] cpusets: confine oom_killer to
mem_exclusive cpuset") introduces a heuristic where a potential
oom-killer victim is skipped if the intersection of the potential victim
and the current (the process triggered the oom) is empty based on the
reason that killing such victim most probably will not help the current
allocating process.

However the commit 7887a3da753e ("[PATCH] oom: cpuset hint") changed the
heuristic to just decrease the oom_badness scores of such potential
victim based on the reason that the cpuset of such processes might have
changed and previously they may have allocated memory on mems where the
current allocating process can allocate from.

Unintentionally 7887a3da753e ("[PATCH] oom: cpuset hint") introduced a
side effect as the oom_badness is also exposed to the user space through
/proc/[pid]/oom_score, so, readers with different cpusets can read
different oom_score of the same process.

Later, commit 6cf86ac6f36b ("oom: filter tasks not sharing the same
cpuset") fixed the side effect introduced by 7887a3da753e by moving the
cpuset intersection back to only oom-killer context and out of
oom_badness. However the combination of ab290adbaf8f ("oom: make
oom_unkillable_task() helper function") and 26ebc984913b ("oom:
/proc/<pid>/oom_score treat kernel thread honestly") unintentionally
brought back the cpuset intersection check into the oom_badness
calculation function.

Other than doing cpuset/mempolicy intersection from oom_badness, the memcg
oom context is also doing cpuset/mempolicy intersection which is quite
wrong and is caught by syzcaller with the following report:

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 28426 Comm: syz-executor.5 Not tainted 5.2.0-rc3-next-20190607
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:__read_once_size include/linux/compiler.h:194 [inline]
RIP: 0010:has_intersects_mems_allowed mm/oom_kill.c:84 [inline]
RIP: 0010:oom_unkillable_task mm/oom_kill.c:168 [inline]
RIP: 0010:oom_unkillable_task+0x180/0x400 mm/oom_kill.c:155
Code: c1 ea 03 80 3c 02 00 0f 85 80 02 00 00 4c 8b a3 10 07 00 00 48 b8 00
00 00 00 00 fc ff df 4d 8d 74 24 10 4c 89 f2 48 c1 ea 03 <80> 3c 02 00 0f
85 67 02 00 00 49 8b 44 24 10 4c 8d a0 68 fa ff ff
RSP: 0018:ffff888000127490 EFLAGS: 00010a03
RAX: dffffc0000000000 RBX: ffff8880a4cd5438 RCX: ffffffff818dae9c
RDX: 100000000c3cc602 RSI: ffffffff818dac8d RDI: 0000000000000001
RBP: ffff8880001274d0 R08: ffff888000086180 R09: ffffed1015d26be0
R10: ffffed1015d26bdf R11: ffff8880ae935efb R12: 8000000061e63007
R13: 0000000000000000 R14: 8000000061e63017 R15: 1ffff11000024ea6
FS: 00005555561f5940(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000607304 CR3: 000000009237e000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
oom_evaluate_task+0x49/0x520 mm/oom_kill.c:321
mem_cgroup_scan_tasks+0xcc/0x180 mm/memcontrol.c:1169
select_bad_process mm/oom_kill.c:374 [inline]
out_of_memory mm/oom_kill.c:1088 [inline]
out_of_memory+0x6b2/0x1280 mm/oom_kill.c:1035
mem_cgroup_out_of_memory+0x1ca/0x230 mm/memcontrol.c:1573
mem_cgroup_oom mm/memcontrol.c:1905 [inline]
try_charge+0xfbe/0x1480 mm/memcontrol.c:2468
mem_cgroup_try_charge+0x24d/0x5e0 mm/memcontrol.c:6073
mem_cgroup_try_charge_delay+0x1f/0xa0 mm/memcontrol.c:6088
do_huge_pmd_wp_page_fallback+0x24f/0x1680 mm/huge_memory.c:1201
do_huge_pmd_wp_page+0x7fc/0x2160 mm/huge_memory.c:1359
wp_huge_pmd mm/memory.c:3793 [inline]
__handle_mm_fault+0x164c/0x3eb0 mm/memory.c:4006
handle_mm_fault+0x3b7/0xa90 mm/memory.c:4053
do_user_addr_fault arch/x86/mm/fault.c:1455 [inline]
__do_page_fault+0x5ef/0xda0 arch/x86/mm/fault.c:1521
do_page_fault+0x71/0x57d arch/x86/mm/fault.c:1552
page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1156
RIP: 0033:0x400590
Code: 06 e9 49 01 00 00 48 8b 44 24 10 48 0b 44 24 28 75 1f 48 8b 14 24 48
8b 7c 24 20 be 04 00 00 00 e8 f5 56 00 00 48 8b 74 24 08 <89> 06 e9 1e 01
00 00 48 8b 44 24 08 48 8b 14 24 be 04 00 00 00 8b
RSP: 002b:00007fff7bc49780 EFLAGS: 00010206
RAX: 0000000000000001 RBX: 0000000000760000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 000000002000cffc RDI: 0000000000000001
RBP: fffffffffffffffe R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000760008
R13: 00000000004c55f2 R14: 0000000000000000 R15: 00007fff7bc499b0
Modules linked in:
---[ end trace a65689219582ffff ]---
RIP: 0010:__read_once_size include/linux/compiler.h:194 [inline]
RIP: 0010:has_intersects_mems_allowed mm/oom_kill.c:84 [inline]
RIP: 0010:oom_unkillable_task mm/oom_kill.c:168 [inline]
RIP: 0010:oom_unkillable_task+0x180/0x400 mm/oom_kill.c:155
Code: c1 ea 03 80 3c 02 00 0f 85 80 02 00 00 4c 8b a3 10 07 00 00 48 b8 00
00 00 00 00 fc ff df 4d 8d 74 24 10 4c 89 f2 48 c1 ea 03 <80> 3c 02 00 0f
85 67 02 00 00 49 8b 44 24 10 4c 8d a0 68 fa ff ff
RSP: 0018:ffff888000127490 EFLAGS: 00010a03
RAX: dffffc0000000000 RBX: ffff8880a4cd5438 RCX: ffffffff818dae9c
RDX: 100000000c3cc602 RSI: ffffffff818dac8d RDI: 0000000000000001
RBP: ffff8880001274d0 R08: ffff888000086180 R09: ffffed1015d26be0
R10: ffffed1015d26bdf R11: ffff8880ae935efb R12: 8000000061e63007
R13: 0000000000000000 R14: 8000000061e63017 R15: 1ffff11000024ea6
FS: 00005555561f5940(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f823000 CR3: 000000009237e000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600

The fix is to decouple the cpuset/mempolicy intersection check from
oom_unkillable_task() and make sure cpuset/mempolicy intersection check is
only done in the global oom context.

[shakeelb@google.com: change function name and update comment]
Link: http://lkml.kernel.org/r/20190628152421.198994-3-shakeelb@google.com
Link: http://lkml.kernel.org/r/20190624212631.87212-3-shakeelb@google.com
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Reported-by: syzbot+d0fc9d3c166bc5e4a94b@syzkaller.appspotmail.com
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Paul Jackson <pj@sgi.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
/linux-master/kernel/
H A Dsysctl.cdiff 67f3977f Mon Sep 23 16:38:47 MDT 2019 Alexandre Ghiti <alex@ghiti.fr> arm64, mm: move generic mmap layout functions to mm

arm64 handles top-down mmap layout in a way that can be easily reused by
other architectures, so make it available in mm. It then introduces a new
config ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT that can be set by other
architectures to benefit from those functions. Note that this new config
depends on MMU being enabled, if selected without MMU support, a warning
will be thrown.

Link: http://lkml.kernel.org/r/20190730055113.23635-5-alex@ghiti.fr
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: James Hogan <jhogan@kernel.org>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff ee9c5785 Sun Apr 20 06:59:33 MDT 2008 Russell King <rmk@dyn-67.arm.linux.org.uk> dyntick: Remove last reminants of dyntick support

Remove the last reminants of dyntick support from the generic kernel.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
/linux-master/include/linux/
H A Dskbuff.hdiff 67f11f4d Sun May 22 18:54:11 MDT 2011 David S. Miller <davem@davemloft.net> net: Remove linux/prefetch.h include from linux/skbuff.h

No longer needed.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff 67fed459 Sun Sep 21 23:36:24 MDT 2008 David S. Miller <davem@davemloft.net> net: Add new interfaces for SKB list light-weight init and splicing.

This will be used by subsequent changesets.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
H A Dfs.hdiff 67cde595 Tue Apr 29 01:58:55 MDT 2008 Adrian Bunk <bunk@kernel.org> make vfs_ioctl() static

Make the needlessly global vfs_ioctl() static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff 67be2dd1 Sun May 01 09:59:26 MDT 2005 Martin Waitz <tali@admingilde.org> [PATCH] DocBook: fix some descriptions

Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Completed in 3700 milliseconds