commit 2761713d35e370fd640b5781109f753066b746c4 upstream.
For write/discard obj_requests that involved a copyup method call, the
opcode of the first op is CEPH_OSD_OP_CALL and the ->callback is
rbd_img_obj_copyup_callback(). The latter frees copyup pages, sets
->xferred and delegates to rbd_img_obj_callback(), the "normal" image
object callback, for reporting to block layer and putting refs.
rbd_osd_req_callback() however treats CEPH_OSD_OP_CALL as a trivial op,
which means obj_request is marked done in rbd_osd_trivial_callback(),
*before* ->callback is invoked and rbd_img_obj_copyup_callback() has
a chance to run. Marking obj_request done essentially means giving
rbd_img_obj_callback() a license to end it at any moment, so if another
obj_request from the same img_request is being completed concurrently,
rbd_img_obj_end_request() may very well be called on such prematurally
marked done request:
<obj_request-1/2 reply>
handle_reply()
rbd_osd_req_callback()
rbd_osd_trivial_callback()
rbd_obj_request_complete()
rbd_img_obj_copyup_callback()
rbd_img_obj_callback()
<obj_request-2/2 reply>
handle_reply()
rbd_osd_req_callback()
rbd_osd_trivial_callback()
for_each_obj_request(obj_request->img_request) {
rbd_img_obj_end_request(obj_request-1/2)
rbd_img_obj_end_request(obj_request-2/2) <--
}
Calling rbd_img_obj_end_request() on such a request leads to trouble,
in particular because its ->xfferred is 0. We report 0 to the block
layer with blk_update_request(), get back 1 for "this request has more
data in flight" and then trip on
rbd_assert(more ^ (which == img_request->obj_request_count));
with rhs (which == ...) being 1 because rbd_img_obj_end_request() has
been called for both requests and lhs (more) being 1 because we haven't
got a chance to set ->xfferred in rbd_img_obj_copyup_callback() yet.
To fix this, leverage that rbd wants to call class methods in only two
cases: one is a generic method call wrapper (obj_request is standalone)
and the other is a copyup (obj_request is part of an img_request). So
make a dedicated handler for CEPH_OSD_OP_CALL and directly invoke
rbd_img_obj_copyup_callback() from it if obj_request is part of an
img_request, similar to how CEPH_OSD_OP_READ handler invokes
rbd_img_obj_request_read_callback().
Since rbd_img_obj_copyup_callback() is now being called from the OSD
request callback (only), it is renamed to rbd_osd_copyup_callback().
Cc: Alex Elder <elder@linaro.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>
[idryomov@gmail.com: backport to < 3.18: context]
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
commit e037239e5e7b61007763984aa35a8329596d8c88 upstream. Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
commit 5c16179b550b9fd8114637a56b153c9768ea06a5 upstream.
The commit
de3910eb79ac ("edac: change the mem allocation scheme to
make Documentation/kobject.txt happy")
changed the memory allocation for the csrows member. But ppc4xx_edac was
forgotten in the patch. Fix it.
Signed-off-by: Michael Walle <michael@walle.cc>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Link: http://lkml.kernel.org/r/1437469253-8611-1-git-send-email-michael@walle.cc
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
commit c0ddc8c745b7f89c50385fd7aa03c78dc543fa7a upstream. In kbuild it is allowed to define objects in files named "Makefile" and "Kbuild". Currently localmodconfig reads objects only from "Makefile"s and misses modules like nouveau. Link: http://lkml.kernel.org/r/1437948415-16290-1-git-send-email-richard@nod.at Reported-and-tested-by: Leonidas Spyropoulos <artafinde@gmail.com> Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
commit 7f518ad0a212e2a6fd68630e176af1de395070a7 upstream. The device details and mapping trees were just being decremented before. Now btree_del() is called to do a deep delete. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
commit fed66e2cdd4f127a43fd11b8d92a99bdd429528c upstream. Vince reported that the fasync signal stuff doesn't work proper for inherited events. So fix that. Installing fasync allocates memory and sets filp->f_flags |= FASYNC, which upon the demise of the file descriptor ensures the allocation is freed and state is updated. Now for perf, we can have the events stick around for a while after the original FD is dead because of references from child events. So we cannot copy the fasync pointer around. We can however consistently use the parent's fasync, as that will be updated. Reported-and-Tested-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho deMelo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: eranian@google.com Link: http://lkml.kernel.org/r/1434011521.1495.71.camel@twins Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
commit 7b0767502b5db11cb1f0daef2d01f6d71b1192dc upstream. We should consider info->feature_persistent when adding indirect page to list info->indirect_pages, else the BUG_ON() in blkif_free() would be triggered. When we are using persistent grants the indirect_pages list should always be empty because blkfront has pre-allocated enough persistent pages to fill all requests on the ring. Acked-by: Roger Pau Monné <roger.pau@citrix.com> Signed-off-by: Bob Liu <bob.liu@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
commit 4f32be677b124a49459e2603321c7a5605ceb9f8 upstream. After trying to drain pages from pagevec/pageset, we try to get reference count of the page again, however, the reference count of the page is not reduced if the page is still not on LRU list. Fix it by adding the put_page() to drop the page reference which is from __get_any_page(). Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
commit 602b8593d2b4138c10e922eeaafe306f6b51817b upstream.
The current semaphore code allows a potential use after free: in
exit_sem we may free the task's sem_undo_list while there is still
another task looping through the same semaphore set and cleaning the
sem_undo list at freeary function (the task called IPC_RMID for the same
semaphore set).
For example, with a test program [1] running which keeps forking a lot
of processes (which then do a semop call with SEM_UNDO flag), and with
the parent right after removing the semaphore set with IPC_RMID, and a
kernel built with CONFIG_SLAB, CONFIG_SLAB_DEBUG and
CONFIG_DEBUG_SPINLOCK, you can easily see something like the following
in the kernel log:
Slab corruption (Not tainted): kmalloc-64 start=ffff88003b45c1c0, len=64
000: 6b 6b 6b 6b 6b 6b 6b 6b 00 6b 6b 6b 6b 6b 6b 6b kkkkkkkk.kkkkkkk
010: ff ff ff ff 6b 6b 6b 6b ff ff ff ff ff ff ff ff ....kkkk........
Prev obj: start=ffff88003b45c180, len=64
000: 00 00 00 00 ad 4e ad de ff ff ff ff 5a 5a 5a 5a .....N......ZZZZ
010: ff ff ff ff ff ff ff ff c0 fb 01 37 00 88 ff ff ...........7....
Next obj: start=ffff88003b45c200, len=64
000: 00 00 00 00 ad 4e ad de ff ff ff ff 5a 5a 5a 5a .....N......ZZZZ
010: ff ff ff ff ff ff ff ff 68 29 a7 3c 00 88 ff ff ........h).<....
BUG: spinlock wrong CPU on CPU#2, test/18028
general protection fault: 0000 [#1] SMP
Modules linked in: 8021q mrp garp stp llc nf_conntrack_ipv4 nf_defrag_ipv4 ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables binfmt_misc ppdev input_leds joydev parport_pc parport floppy serio_raw virtio_balloon virtio_rng virtio_console virtio_net iosf_mbi crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcspkr qxl ttm drm_kms_helper drm snd_hda_codec_generic i2c_piix4 snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer snd soundcore crc32c_intel virtio_pci virtio_ring virtio pata_acpi ata_generic [last unloaded: speedstep_lib]
CPU: 2 PID: 18028 Comm: test Not tainted 4.2.0-rc5+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014
RIP: spin_dump+0x53/0xc0
Call Trace:
spin_bug+0x30/0x40
do_raw_spin_unlock+0x71/0xa0
_raw_spin_unlock+0xe/0x10
freeary+0x82/0x2a0
? _raw_spin_lock+0xe/0x10
semctl_down.clone.0+0xce/0x160
? __do_page_fault+0x19a/0x430
? __audit_syscall_entry+0xa8/0x100
SyS_semctl+0x236/0x2c0
? syscall_trace_leave+0xde/0x130
entry_SYSCALL_64_fastpath+0x12/0x71
Code: 8b 80 88 03 00 00 48 8d 88 60 05 00 00 48 c7 c7 a0 2c a4 81 31 c0 65 8b 15 eb 40 f3 7e e8 08 31 68 00 4d 85 e4 44 8b 4b 08 74 5e <45> 8b 84 24 88 03 00 00 49 8d 8c 24 60 05 00 00 8b 53 04 48 89
RIP [<ffffffff810d6053>] spin_dump+0x53/0xc0
RSP <ffff88003750fd68>
---[ end trace 783ebb76612867a0 ]---
NMI watchdog: BUG: soft lockup - CPU#3 stuck for 22s! [test:18053]
Modules linked in: 8021q mrp garp stp llc nf_conntrack_ipv4 nf_defrag_ipv4 ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables binfmt_misc ppdev input_leds joydev parport_pc parport floppy serio_raw virtio_balloon virtio_rng virtio_console virtio_net iosf_mbi crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcspkr qxl ttm drm_kms_helper drm snd_hda_codec_generic i2c_piix4 snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer snd soundcore crc32c_intel virtio_pci virtio_ring virtio pata_acpi ata_generic [last unloaded: speedstep_lib]
CPU: 3 PID: 18053 Comm: test Tainted: G D 4.2.0-rc5+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014
RIP: native_read_tsc+0x0/0x20
Call Trace:
? delay_tsc+0x40/0x70
__delay+0xf/0x20
do_raw_spin_lock+0x96/0x140
_raw_spin_lock+0xe/0x10
sem_lock_and_putref+0x11/0x70
SYSC_semtimedop+0x7bf/0x960
? handle_mm_fault+0xbf6/0x1880
? dequeue_task_fair+0x79/0x4a0
? __do_page_fault+0x19a/0x430
? kfree_debugcheck+0x16/0x40
? __do_page_fault+0x19a/0x430
? __audit_syscall_entry+0xa8/0x100
? do_audit_syscall_entry+0x66/0x70
? syscall_trace_enter_phase1+0x139/0x160
SyS_semtimedop+0xe/0x10
SyS_semop+0x10/0x20
entry_SYSCALL_64_fastpath+0x12/0x71
Code: 47 10 83 e8 01 85 c0 89 47 10 75 08 65 48 89 3d 1f 74 ff 7e c9 c3 0f 1f 44 00 00 55 48 89 e5 e8 87 17 04 00 66 90 c9 c3 0f 1f 00 <55> 48 89 e5 0f 31 89 c1 48 89 d0 48 c1 e0 20 89 c9 48 09 c8 c9
Kernel panic - not syncing: softlockup: hung tasks
I wasn't able to trigger any badness on a recent kernel without the
proper config debugs enabled, however I have softlockup reports on some
kernel versions, in the semaphore code, which are similar as above (the
scenario is seen on some servers running IBM DB2 which uses semaphore
syscalls).
The patch here fixes the race against freeary, by acquiring or waiting
on the sem_undo_list lock as necessary (exit_sem can race with freeary,
while freeary sets un->semid to -1 and removes the same sem_undo from
list_proc or when it removes the last sem_undo).
After the patch I'm unable to reproduce the problem using the test case
[1].
[1] Test case used below:
#include <stdio.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/sem.h>
#include <sys/wait.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>
#include <errno.h>
#define NSEM 1
#define NSET 5
int sid[NSET];
void thread()
{
struct sembuf op;
int s;
uid_t pid = getuid();
s = rand() % NSET;
op.sem_num = pid % NSEM;
op.sem_op = 1;
op.sem_flg = SEM_UNDO;
semop(sid[s], &op, 1);
exit(EXIT_SUCCESS);
}
void create_set()
{
int i, j;
pid_t p;
union {
int val;
struct semid_ds *buf;
unsigned short int *array;
struct seminfo *__buf;
} un;
/* Create and initialize semaphore set */
for (i = 0; i < NSET; i++) {
sid[i] = semget(IPC_PRIVATE , NSEM, 0644 | IPC_CREAT);
if (sid[i] < 0) {
perror("semget");
exit(EXIT_FAILURE);
}
}
un.val = 0;
for (i = 0; i < NSET; i++) {
for (j = 0; j < NSEM; j++) {
if (semctl(sid[i], j, SETVAL, un) < 0)
perror("semctl");
}
}
/* Launch threads that operate on semaphore set */
for (i = 0; i < NSEM * NSET * NSET; i++) {
p = fork();
if (p < 0)
perror("fork");
if (p == 0)
thread();
}
/* Free semaphore set */
for (i = 0; i < NSET; i++) {
if (semctl(sid[i], NSEM, IPC_RMID))
perror("IPC_RMID");
}
/* Wait for forked processes to exit */
while (wait(NULL)) {
if (errno == ECHILD)
break;
};
}
int main(int argc, char **argv)
{
pid_t p;
srand(time(NULL));
while (1) {
p = fork();
if (p < 0) {
perror("fork");
exit(EXIT_FAILURE);
}
if (p == 0) {
create_set();
goto end;
}
/* Wait for forked processes to exit */
while (wait(NULL)) {
if (errno == ECHILD)
break;
};
}
end:
return 0;
}
[akpm@linux-foundation.org: use normal comment layout]
Signed-off-by: Herton R. Krzesinski <herton@redhat.com>
Acked-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Rafael Aquini <aquini@redhat.com>
CC: Aristeu Rozanski <aris@redhat.com>
Cc: David Jeffery <djeffery@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>