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2018-06-08block: add bioset_init_from_src() helperJens Axboe2-0/+19
Add a helper that allows a caller to initialize a new bio_set, using the settings from an existing bio_set. Reported-by: Venkat R.B <[email protected]> Tested-by: Venkat R.B <[email protected]> Tested-by: Li Wang <[email protected]> Reviewed-by: Mike Snitzer <[email protected]> Signed-off-by: Jens Axboe <[email protected]>
2018-06-08arm64: Fix syscall restarting around signal suppressed by tracerDave Martin1-2/+3
Commit 17c2895 ("arm64: Abstract syscallno manipulation") abstracts out the pt_regs.syscallno value for a syscall cancelled by a tracer as NO_SYSCALL, and provides helpers to set and check for this condition. However, the way this was implemented has the unintended side-effect of disabling part of the syscall restart logic. This comes about because the second in_syscall() check in do_signal() re-evaluates the "in a syscall" condition based on the updated pt_regs instead of the original pt_regs. forget_syscall() is explicitly called prior to the second check in order to prevent restart logic in the ret_to_user path being spuriously triggered, which means that the second in_syscall() check always yields false. This triggers a failure in tools/testing/selftests/seccomp/seccomp_bpf.c, when using ptrace to suppress a signal that interrups a nanosleep() syscall. Misbehaviour of this type is only expected in the case where a tracer suppresses a signal and the target process is either being single-stepped or the interrupted syscall attempts to restart via -ERESTARTBLOCK. This patch restores the old behaviour by performing the in_syscall() check only once at the start of the function. Fixes: 17c289586009 ("arm64: Abstract syscallno manipulation") Signed-off-by: Dave Martin <[email protected]> Reported-by: Sumit Semwal <[email protected]> Cc: Will Deacon <[email protected]> Cc: <[email protected]> # 4.14.x- Signed-off-by: Catalin Marinas <[email protected]>
2018-06-08Merge branch 'for-4.18/wacom' into for-linusJiri Kosina1-35/+39
Support for "In Range" flag for Wacom Intuos/Bamboo devices from Jason Gerecke
2018-06-08Merge branch 'for-4.18/upstream' into for-linusJiri Kosina1-1/+0
2018-06-08Merge branch 'for-4.18/rmi' into for-linusJiri Kosina1-0/+20
RMI4 correct split report handling from Benjamin Tissoires
2018-06-08Merge branch 'for-4.18/plantronics' into for-linusJiri Kosina1-1/+5
2018-06-08Merge branch 'for-4.18/multitouch' into for-linusJiri Kosina7-134/+281
- improvement of duplicate usage handling in hid-input from Benjamin Tissoires - Win 8.1 precisioun touchpad spec implementation from Benjamin Tissoires
2018-06-08Merge branch 'for-4.18/i2c-hid' into for-linusJiri Kosina1-8/+25
Assorted smaller fixes to i2c-hid driver
2018-06-08Merge branch 'for-4.18/hid-steam' into for-linusJiri Kosina961-5217/+10338
Valve Steam Controller support from Rodrigo Rivas Costa
2018-06-08Merge branch 'for-4.18/hid-redragon' into for-linusJiri Kosina4-0/+95
Redragon Asura support from Robert Munteanu
2018-06-08Merge branch 'for-4.18/alps' into for-linusJiri Kosina4603-104485/+178005
hid-alps driver cleanups wrt. t4_read_write_register() handling from Christophe Jaillet
2018-06-08fix proc_fill_cache() in case of d_alloc_parallel() failureAl Viro1-3/+3
If d_alloc_parallel() returns ERR_PTR(...), we don't want to dput() that. Small reorganization allows to have all error-in-lookup cases rejoin the main codepath after dput(child), avoiding the entire problem. Spotted-by: Tetsuo Handa <[email protected]> Fixes: 0168b9e38c42 "procfs: switch instantiate_t to d_splice_alias()" Signed-off-by: Al Viro <[email protected]>
2018-06-07Merge branch 'akpm' (patches from Andrew)Linus Torvalds147-2066/+2945
Merge updates from Andrew Morton: - a few misc things - ocfs2 updates - v9fs updates - MM - procfs updates - lib/ updates - autofs updates * emailed patches from Andrew Morton <[email protected]>: (118 commits) autofs: small cleanup in autofs_getpath() autofs: clean up includes autofs: comment on selinux changes needed for module autoload autofs: update MAINTAINERS entry for autofs autofs: use autofs instead of autofs4 in documentation autofs: rename autofs documentation files autofs: create autofs Kconfig and Makefile autofs: delete fs/autofs4 source files autofs: update fs/autofs4/Makefile autofs: update fs/autofs4/Kconfig autofs: copy autofs4 to autofs autofs4: use autofs instead of autofs4 everywhere autofs4: merge auto_fs.h and auto_fs4.h fs/binfmt_misc.c: do not allow offset overflow checkpatch: improve patch recognition lib/ucs2_string.c: add MODULE_LICENSE() lib/mpi: headers cleanup lib/percpu_ida.c: use _irqsave() instead of local_irq_save() + spin_lock lib/idr.c: remove simple_ida_lock lib/bitmap.c: micro-optimization for __bitmap_complement() ...
2018-06-07autofs: small cleanup in autofs_getpath()Dan Carpenter1-3/+3
We don't set "*name" so it's slightly nicer to just pass "name" instead of "&name". Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Dan Carpenter <[email protected]> Acked-by: "Eric W. Biederman" <[email protected]> Acked-by: Ian Kent <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07autofs: clean up includesIan Kent6-30/+2
Remove includes that aren't needed from autofs (and fs/compat_ioctl.c). Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ian Kent <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07autofs: comment on selinux changes needed for module autoloadIan Kent1-0/+6
Due to the autofs4 module using a file system type name of autofs different from the module containing directory name autoload did not function properly. To work around this kernel configurations have often elected to build the module into the kernel. This can result in selinux policies that prohibit autoloading of the autofs module which need to be changed. Add a comment about this to "possible changes" section of the autofs4 module help. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ian Kent <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07autofs: update MAINTAINERS entry for autofsIan Kent1-2/+2
Update the autofs entry in MAINTAINERS to reflect the rename of autofs4 to autofs. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ian Kent <[email protected]> Cc: Al Viro <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07autofs: use autofs instead of autofs4 in documentationIan Kent5-13/+13
Finally remove autofs4 references in the filesystems documentation. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ian Kent <[email protected]> Cc: Al Viro <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07autofs: rename autofs documentation filesIan Kent2-1/+0
There are two files in Documentation/filsystems that should now use autofs rather than autofs4 in their names. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ian Kent <[email protected]> Cc: Al Viro <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07autofs: create autofs Kconfig and MakefileIan Kent5-0/+37
Create Makefile and Kconfig for autofs module. [[email protected]: make autofs4 Kconfig depend on AUTOFS_FS] Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ian Kent <[email protected]> Tested-by: Randy Dunlap <[email protected]> Cc: Al Viro <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07autofs: delete fs/autofs4 source filesIan Kent8-3619/+0
Delete the now unused autofs4 module files. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ian Kent <[email protected]> Cc: Al Viro <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07autofs: update fs/autofs4/MakefileIan Kent1-1/+3
Update Makefile to build from source in fs/autofs instead of fs/autofs4. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ian Kent <[email protected]> Cc: Al Viro <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07autofs: update fs/autofs4/KconfigIan Kent1-10/+22
Update Kconfig and add a depricated warning. [[email protected]: make autofs4 Kconfig depend on AUTOFS_FS] Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ian Kent <[email protected]> Tested-by: Randy Dunlap <[email protected]> Cc: Al Viro <[email protected]> Cc: Arnd Bergmann <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07autofs: copy autofs4 to autofsIan Kent8-0/+3618
Copy source files from the autofs4 directory to the autofs directory. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ian Kent <[email protected]> Cc: Al Viro <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07autofs4: use autofs instead of autofs4 everywhereIan Kent8-319/+319
Update naming within autofs source to be consistent by changing occurrences of autofs4 to autofs. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ian Kent <[email protected]> Cc: Al Viro <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07autofs4: merge auto_fs.h and auto_fs4.hIan Kent4-164/+161
The autofs module has long since been removed so there's no need to have two separate include files for autofs. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ian Kent <[email protected]> Cc: Al Viro <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07fs/binfmt_misc.c: do not allow offset overflowThadeu Lima de Souza Cascardo1-3/+9
WHen registering a new binfmt_misc handler, it is possible to overflow the offset to get a negative value, which might crash the system, or possibly leak kernel data. Here is a crash log when 2500000000 was used as an offset: BUG: unable to handle kernel paging request at ffff989cfd6edca0 IP: load_misc_binary+0x22b/0x470 [binfmt_misc] PGD 1ef3e067 P4D 1ef3e067 PUD 0 Oops: 0000 [#1] SMP NOPTI Modules linked in: binfmt_misc kvm_intel ppdev kvm irqbypass joydev input_leds serio_raw mac_hid parport_pc qemu_fw_cfg parpy CPU: 0 PID: 2499 Comm: bash Not tainted 4.15.0-22-generic #24-Ubuntu Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.1-1 04/01/2014 RIP: 0010:load_misc_binary+0x22b/0x470 [binfmt_misc] Call Trace: search_binary_handler+0x97/0x1d0 do_execveat_common.isra.34+0x667/0x810 SyS_execve+0x31/0x40 do_syscall_64+0x73/0x130 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 Use kstrtoint instead of simple_strtoul. It will work as the code already set the delimiter byte to '\0' and we only do it when the field is not empty. Tested with offsets -1, 2500000000, UINT_MAX and INT_MAX. Also tested with examples documented at Documentation/admin-guide/binfmt-misc.rst and other registrations from packages on Ubuntu. Link: http://lkml.kernel.org/r/[email protected] Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Thadeu Lima de Souza Cascardo <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Cc: Alexander Viro <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07checkpatch: improve patch recognitionJoe Perches1-0/+8
There are mode change and rename only patches that are unrecognized by checkpatch. Recognize them. [[email protected]: fix missing close parenthesis] Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/974a407e6fa18abd5a965da39cc68986a4c4f091.1526949367.git.joe@perches.com Signed-off-by: Joe Perches <[email protected]> Reported-by: Heinrich Schuchardt <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07lib/ucs2_string.c: add MODULE_LICENSE()Randy Dunlap1-0/+2
Fix missing MODULE_LICENSE() warning in lib/ucs2_string.c: WARNING: modpost: missing MODULE_LICENSE() in lib/ucs2_string.o see include/linux/module.h for more information Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Randy Dunlap <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Matthew Garrett <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07lib/mpi: headers cleanupVasily Averin2-131/+5
MPI headers contain definitions for huge number of non-existing functions. Most part of these functions was removed in 2012 by Dmitry Kasatkin - 7cf4206a99d1 ("Remove unused code from MPI library") - 9e235dcaf4f6 ("Revert "crypto: GnuPG based MPI lib - additional ...") - bc95eeadf5c6 ("lib/mpi: removed unused functions") however headers wwere not updated properly. Also I deleted some unused macros. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Vasily Averin <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Cc: Dmitry Kasatkin <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07lib/percpu_ida.c: use _irqsave() instead of local_irq_save() + spin_lockSebastian Andrzej Siewior1-42/+21
percpu_ida() decouples disabling interrupts from the locking operations. This breaks some assumptions if the locking operations are replaced like they are under -RT. The same locking can be achieved by avoiding local_irq_save() and using spin_lock_irqsave() instead. percpu_ida_alloc() gains one more preemption point because after unlocking the fastpath and before the pool lock is acquired, the interrupts are briefly enabled. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Sebastian Andrzej Siewior <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Nicholas Bellinger <[email protected]> Cc: Shaohua Li <[email protected]> Cc: Kent Overstreet <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Jens Axboe <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07lib/idr.c: remove simple_ida_lockMatthew Wilcox1-5/+5
Improve the scalability of the IDA by using the per-IDA xa_lock rather than the global simple_ida_lock. IDAs are not typically used in performance-sensitive locations, but since we have this lock anyway, we can use it. It is also a step towards converting the IDA from the radix tree to the XArray. [[email protected]: idr.c needs xarray.h] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Matthew Wilcox <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Cc: Rasmus Villemoes <[email protected]> Cc: Daniel Vetter <[email protected]> Cc: Tejun Heo <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07lib/bitmap.c: micro-optimization for __bitmap_complement()Yury Norov1-4/+1
Use BITS_TO_LONGS() macro to avoid calculation of reminder (bits % BITS_PER_LONG) On ARM64 it saves 5 instruction for function - 16 before and 11 after. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Yury Norov <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Rasmus Villemoes <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07get_maintainer: improve patch recognitionJoe Perches1-1/+12
There are mode change and rename only patches that are unrecognized by the get_maintainer.pl script. Recognize them. Link: http://lkml.kernel.org/r/bf63101a908d0ff51948164aa60e672368066186.1526949367.git.joe@perches.com Signed-off-by: Joe Perches <[email protected]> Reported-by: Heinrich Schuchardt <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07kernel/hung_task.c: show all hung tasks before panicTetsuo Handa1-4/+7
When we get a hung task it can often be valuable to see _all_ the hung tasks on the system before calling panic(). Quoting from https://syzkaller.appspot.com/text?tag=CrashReport&id=5316056503549952 ---------------------------------------- INFO: task syz-executor0:6540 blocked for more than 120 seconds. Not tainted 4.16.0+ #13 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D23560 6540 4521 0x80000004 Call Trace: context_switch kernel/sched/core.c:2848 [inline] __schedule+0x8fb/0x1ef0 kernel/sched/core.c:3490 schedule+0xf5/0x430 kernel/sched/core.c:3549 schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:3607 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0xb7f/0x1810 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 lo_ioctl+0x8b/0x1b70 drivers/block/loop.c:1355 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0x1759/0x1e00 block/ioctl.c:601 ioctl_by_bdev+0xa5/0x110 fs/block_dev.c:2060 isofs_get_last_session fs/isofs/inode.c:567 [inline] isofs_fill_super+0x2ba9/0x3bc0 fs/isofs/inode.c:660 mount_bdev+0x2b7/0x370 fs/super.c:1119 isofs_mount+0x34/0x40 fs/isofs/inode.c:1560 mount_fs+0x66/0x2d0 fs/super.c:1222 vfs_kern_mount.part.26+0xc6/0x4a0 fs/namespace.c:1037 vfs_kern_mount fs/namespace.c:2514 [inline] do_new_mount fs/namespace.c:2517 [inline] do_mount+0xea4/0x2b90 fs/namespace.c:2847 ksys_mount+0xab/0x120 fs/namespace.c:3063 SYSC_mount fs/namespace.c:3077 [inline] SyS_mount+0x39/0x50 fs/namespace.c:3074 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 (...snipped...) Showing all locks held in the system: (...snipped...) 2 locks held by syz-executor0/6540: #0: 00000000566d4c39 (&type->s_umount_key#49/1){+.+.}, at: alloc_super fs/super.c:211 [inline] #0: 00000000566d4c39 (&type->s_umount_key#49/1){+.+.}, at: sget_userns+0x3b2/0xe60 fs/super.c:502 /* down_write_nested(&s->s_umount, SINGLE_DEPTH_NESTING); */ #1: 0000000043ca8836 (&lo->lo_ctl_mutex/1){+.+.}, at: lo_ioctl+0x8b/0x1b70 drivers/block/loop.c:1355 /* mutex_lock_nested(&lo->lo_ctl_mutex, 1); */ (...snipped...) 3 locks held by syz-executor7/6541: #0: 0000000043ca8836 (&lo->lo_ctl_mutex/1){+.+.}, at: lo_ioctl+0x8b/0x1b70 drivers/block/loop.c:1355 /* mutex_lock_nested(&lo->lo_ctl_mutex, 1); */ #1: 000000007bf3d3f9 (&bdev->bd_mutex){+.+.}, at: blkdev_reread_part+0x1e/0x40 block/ioctl.c:192 #2: 00000000566d4c39 (&type->s_umount_key#50){.+.+}, at: __get_super.part.10+0x1d3/0x280 fs/super.c:663 /* down_read(&sb->s_umount); */ ---------------------------------------- When reporting an AB-BA deadlock like shown above, it would be nice if trace of PID=6541 is printed as well as trace of PID=6540 before calling panic(). Showing hung tasks up to /proc/sys/kernel/hung_task_warnings could delay calling panic() but normally there should not be so many hung tasks. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Tetsuo Handa <[email protected]> Acked-by: Paul E. McKenney <[email protected]> Acked-by: Dmitry Vyukov <[email protected]> Cc: Vegard Nossum <[email protected]> Cc: Mandeep Singh Baines <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07include/linux/types.h: use fixed width types without double-underscore prefixMasahiro Yamada1-14/+14
This header file is not exported. It is safe to reference types without double-underscore prefix. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Masahiro Yamada <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Alexey Dobriyan <[email protected]> Cc: Lihao Liang <[email protected]> Cc: Philippe Ombredanne <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07include/linux/types.h: define aligned_ types based on uapi headerMasahiro Yamada1-3/+3
<uapi/linux/types.h> has the same typedefs except that it prefixes them with double-underscore for user space. Use them for the kernel space typedefs. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Masahiro Yamada <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Alexey Dobriyan <[email protected]> Cc: Lihao Liang <[email protected]> Cc: Philippe Ombredanne <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07int-ll64.h: define u{8,16,32,64} and s{8,16,32,64} based on uapi headerMasahiro Yamada1-11/+8
<uapi/asm-generic/int-ll64.h> has the same typedefs except that it prefixes them with double-underscore for user space. Use them for the kernel space typedefs. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Masahiro Yamada <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Alexey Dobriyan <[email protected]> Cc: Lihao Liang <[email protected]> Cc: Philippe Ombredanne <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07tools/testing/selftests/proc: test /proc/*/fd a bit (+ PF_KTHREAD is ABI!)Alexey Dobriyan8-32/+451
* Test lookup in /proc/self/fd. "map_files" lookup story showed that lookup is not that simple. * Test that all those symlinks open the same file. Check with (st_dev, st_info). * Test that kernel threads do not have anything in their /proc/*/fd/ directory. Now this is where things get interesting. First, kernel threads aren't pinned by /proc/self or equivalent, thus some "atomicity" is required. Second, ->comm can contain whitespace and ')'. No, they are not escaped. Third, the only reliable way to check if process is kernel thread appears to be field #9 in /proc/*/stat. This field is struct task_struct::flags in decimal! Check is done by testing PF_KTHREAD flags like we do in kernel. PF_KTREAD value is a part of userspace ABI !!! Other methods for determining kernel threadness are not reliable: * RSS can be 0 if everything is swapped, even while reading from /proc/self. * ->total_vm CAN BE ZERO if process is finishing munmap(NULL, whole address space); * /proc/*/maps and similar files can be empty because unmapping everything works. Read returning 0 can't distinguish between kernel thread and such suicide process. Link: http://lkml.kernel.org/r/20180505000414.GA15090@avx2 Signed-off-by: Alexey Dobriyan <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07proc: use "unsigned int" for /proc/*/stackAlexey Dobriyan1-1/+2
struct stack_trace::nr_entries is defined as "unsigned int" (YAY!) so the iterator should be unsigned as well. It saves 1 byte of code or something like that. Link: http://lkml.kernel.org/r/20180423215248.GG9043@avx2 Signed-off-by: Alexey Dobriyan <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Cc: Al Viro <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07proc: use "unsigned int" for sigqueue lengthAlexey Dobriyan1-1/+1
It's defined as atomic_t and really long signal queues are unheard of. Link: http://lkml.kernel.org/r/20180423215119.GF9043@avx2 Signed-off-by: Alexey Dobriyan <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Cc: Al Viro <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07proc: use "unsigned int" in proc_fill_cache()Alexey Dobriyan3-5/+5
All those lengths are unsigned as they should be. Link: http://lkml.kernel.org/r/20180423213751.GC9043@avx2 Signed-off-by: Alexey Dobriyan <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Cc: Al Viro <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07proc: smaller RCU section in ->getattr()Alexey Dobriyan1-1/+1
struct kstat is thread local. Link: http://lkml.kernel.org/r/20180423213626.GB9043@avx2 Signed-off-by: Alexey Dobriyan <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Cc: Al Viro <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07proc: deduplicate /proc/*/cmdline implementationAlexey Dobriyan1-33/+20
Code can be sonsolidated if a dummy region of 0 length is used in normal case of \0-separated command line: 1) [arg_start, arg_end) + [dummy len=0] 2) [arg_start, arg_end) + [env_start, env_end) Link: http://lkml.kernel.org/r/20180221193335.GB28678@avx2 Signed-off-by: Alexey Dobriyan <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Cc: Andy Shevchenko <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07proc: simpler iterations for /proc/*/cmdlineAlexey Dobriyan1-19/+14
"rv" variable is used both as a counter of bytes transferred and an error value holder but it can be reduced solely to error values if original start of userspace buffer is stashed and used at the very end. [[email protected]: simplify cleanup code] Link: http://lkml.kernel.org/r/20180221193009.GA28678@avx2 Signed-off-by: Alexey Dobriyan <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Cc: Andy Shevchenko <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07proc: somewhat simpler code for /proc/*/cmdlineAlexey Dobriyan1-15/+9
"final" variable is OK but we can get away with less lines. Link: http://lkml.kernel.org/r/20180221192751.GC28548@avx2 Signed-off-by: Alexey Dobriyan <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Cc: Andy Shevchenko <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07proc: more "unsigned int" in /proc/*/cmdlineAlexey Dobriyan1-17/+12
access_remote_vm() doesn't return negative errors, it returns number of bytes read/written (0 if error occurs). This allows to delete some comparisons which never trigger. Reuse "nr_read" variable while I'm at it. Link: http://lkml.kernel.org/r/20180221192605.GB28548@avx2 Signed-off-by: Alexey Dobriyan <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Cc: Andy Shevchenko <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07mm: remove page_is_poisoned() from linux/mm.hSahara1-2/+0
When commit bd33ef368135 ("mm: enable page poisoning early at boot") got rid of the PAGE_EXT_DEBUG_POISON, page_is_poisoned in the header left behind. This patch cleans up the leftovers under the table. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Sahara <[email protected]> Acked-by: Michal Hocko <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07mem_cgroup: make sure moving_account, move_lock_task and stat_cpu in the ↵Aaron Lu1-4/+19
same cacheline The LKP robot found a 27% will-it-scale/page_fault3 performance regression regarding commit e27be240df53("mm: memcg: make sure memory.events is uptodate when waking pollers"). What the test does is: 1 mkstemp() a 128M file on a tmpfs; 2 start $nr_cpu processes, each to loop the following: 2.1 mmap() this file in shared write mode; 2.2 write 0 to this file in a PAGE_SIZE step till the end of the file; 2.3 unmap() this file and repeat this process. 3 After 5 minutes, check how many loops they managed to complete, the higher the better. The commit itself looks innocent enough as it merely changed some event counting mechanism and this test didn't trigger those events at all. Perf shows increased cycles spent on accessing root_mem_cgroup->stat_cpu in count_memcg_event_mm()(called by handle_mm_fault()) and in __mod_memcg_state() called by page_add_file_rmap(). So it's likely due to the changed layout of 'struct mem_cgroup' that either make stat_cpu falling into a constantly modifying cacheline or some hot fields stop being in the same cacheline. I verified this by moving memory_events[] back to where it was: : --- a/include/linux/memcontrol.h : +++ b/include/linux/memcontrol.h : @@ -205,7 +205,6 @@ struct mem_cgroup { : int oom_kill_disable; : : /* memory.events */ : - atomic_long_t memory_events[MEMCG_NR_MEMORY_EVENTS]; : struct cgroup_file events_file; : : /* protect arrays of thresholds */ : @@ -238,6 +237,7 @@ struct mem_cgroup { : struct mem_cgroup_stat_cpu __percpu *stat_cpu; : atomic_long_t stat[MEMCG_NR_STAT]; : atomic_long_t events[NR_VM_EVENT_ITEMS]; : + atomic_long_t memory_events[MEMCG_NR_MEMORY_EVENTS]; : : unsigned long socket_pressure; And performance restored. Later investigation found that as long as the following 3 fields moving_account, move_lock_task and stat_cpu are in the same cacheline, performance will be good. To avoid future performance surprise by other commits changing the layout of 'struct mem_cgroup', this patch makes sure the 3 fields stay in the same cacheline. One concern of this approach is, moving_account and move_lock_task could be modified when a process changes memory cgroup while stat_cpu is a always read field, it might hurt to place them in the same cacheline. I assume it is rare for a process to change memory cgroup so this should be OK. Link: https://lkml.kernel.org/r/20180528114019.GF9904@yexl-desktop Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Aaron Lu <[email protected]> Reported-by: kernel test robot <[email protected]> Cc: Johannes Weiner <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Tejun Heo <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-06-07mm: kvmalloc does not fallback to vmalloc for incompatible gfp flagsMichal Hocko2-6/+5
kvmalloc warned about incompatible gfp_mask to catch abusers (mostly GFP_NOFS) with an intention that this will motivate authors of the code to fix those. Linus argues that this just motivates people to do even more hacks like if (gfp == GFP_KERNEL) kvmalloc else kmalloc I haven't seen this happening much (Linus pointed to bucket_lock special cases an atomic allocation but my git foo hasn't found much more) but it is true that we can grow those in future. Therefore Linus suggested to simply not fallback to vmalloc for incompatible gfp flags and rather stick with the kmalloc path. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Michal Hocko <[email protected]> Suggested-by: Linus Torvalds <[email protected]> Cc: Tom Herbert <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
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