Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
[ Upstream commit 3017cd63f26fc655d56875aaf497153ba60e9edf ]
With netconsole (at least) the pr_err("... disablingn") call can
recurse back into the dma-debug code, where it'll try to grab
free_entries_lock again. Avoid the problem by doing the printk after
dropping the lock.
Link: http://lkml.kernel.org/r/1463678421-18683-1-git-send-email-ville.syrjala@linux.intel.com
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
[ Upstream commit 1900149c835ab5b48bea31a823ea5e5a401fb560 ] Ezequiel reported that he's facing UBI going into read-only mode after power cut. It turned out that this behavior happens only when updating a static volume is interrupted and Fastmap is used. A possible trace can look like: ubi0 warning: ubi_io_read_vid_hdr [ubi]: no VID header found at PEB 2323, only 0xFF bytes ubi0 warning: ubi_eba_read_leb [ubi]: switch to read-only mode CPU: 0 PID: 833 Comm: ubiupdatevol Not tainted 4.6.0-rc2-ARCH #4 Hardware name: SAMSUNG ELECTRONICS CO., LTD. 300E4C/300E5C/300E7C/NP300E5C-AD8AR, BIOS P04RAP 10/15/2012 0000000000000286 00000000eba949bd ffff8800c45a7b38 ffffffff8140d841 ffff8801964be000 ffff88018eaa4800 ffff8800c45a7bb8 ffffffffa003abf6 ffffffff850e2ac0 8000000000000163 ffff8801850e2ac0 ffff8801850e2ac0 Call Trace: [<ffffffff8140d841>] dump_stack+0x63/0x82 [<ffffffffa003abf6>] ubi_eba_read_leb+0x486/0x4a0 [ubi] [<ffffffffa00453b3>] ubi_check_volume+0x83/0xf0 [ubi] [<ffffffffa0039d97>] ubi_open_volume+0x177/0x350 [ubi] [<ffffffffa00375d8>] vol_cdev_open+0x58/0xb0 [ubi] [<ffffffff8124b08e>] chrdev_open+0xae/0x1d0 [<ffffffff81243bcf>] do_dentry_open+0x1ff/0x300 [<ffffffff8124afe0>] ? cdev_put+0x30/0x30 [<ffffffff81244d36>] vfs_open+0x56/0x60 [<ffffffff812545f4>] path_openat+0x4f4/0x1190 [<ffffffff81256621>] do_filp_open+0x91/0x100 [<ffffffff81263547>] ? __alloc_fd+0xc7/0x190 [<ffffffff812450df>] do_sys_open+0x13f/0x210 [<ffffffff812451ce>] SyS_open+0x1e/0x20 [<ffffffff81a99e32>] entry_SYSCALL_64_fastpath+0x1a/0xa4 UBI checks static volumes for data consistency and reads the whole volume upon first open. If the volume is found erroneous users of UBI cannot read from it, but another volume update is possible to fix it. The check is performed by running ubi_eba_read_leb() on every allocated LEB of the volume. For static volumes ubi_eba_read_leb() computes the checksum of all data stored in a LEB. To verify the computed checksum it has to read the LEB's volume header which stores the original checksum. If the volume header is not found UBI treats this as fatal internal error and switches to RO mode. If the UBI device was attached via a full scan the assumption is correct, the volume header has to be present as it had to be there while scanning to get known as mapped. If the attach operation happened via Fastmap the assumption is no longer correct. When attaching via Fastmap UBI learns the mapping table from Fastmap's snapshot of the system state and not via a full scan. It can happen that a LEB got unmapped after a Fastmap was written to the flash. Then UBI can learn the LEB still as mapped and accessing it returns only 0xFF bytes. As UBI is not a FTL it is allowed to have mappings to empty PEBs, it assumes that the layer above takes care of LEB accounting and referencing. UBIFS does so using the LEB property tree (LPT). For static volumes UBI blindly assumes that all LEBs are present and therefore special actions have to be taken. The described situation can happen when updating a static volume is interrupted, either by a user or a power cut. The volume update code first unmaps all LEBs of a volume and then writes LEB by LEB. If the sequence of operations is interrupted UBI detects this either by the absence of LEBs, no volume header present at scan time, or corrupted payload, detected via checksum. In the Fastmap case the former method won't trigger as no scan happened and UBI automatically thinks all LEBs are present. Only by reading data from a LEB it detects that the volume header is missing and incorrectly treats this as fatal error. To deal with the situation ubi_eba_read_leb() from now on checks whether we attached via Fastmap and handles the absence of a volume header like a data corruption error. This way interrupted static volume updates will correctly get detected also when Fastmap is used. Cc: <stable@vger.kernel.org> Reported-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> Tested-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
[ Upstream commit b388e6a7a6ba988998ddd83919ae8d3debf1a13d ]
commit 0e707ae79ba3 ("UBI: do propagate positive error codes up") seems
to have produced an unintended change in the control flow here.
Completely untested, but it looks obvious.
Caught by Coverity, which didn't like the indentation. CID 1271184.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
[ Upstream commit 0e707ae79ba357d60b8a36025ec8968e5020d827 ]
UBI uses positive function return codes internally, and should not propagate
them up, except in the place this path fixes. Here is the original bug report
from Dan Carpenter:
The problem is really in ubi_eba_read_leb().
drivers/mtd/ubi/eba.c
412 err = ubi_io_read_vid_hdr(ubi, pnum, vid_hdr, 1);
413 if (err && err != UBI_IO_BITFLIPS) {
414 if (err > 0) {
415 /*
416 * The header is either absent or corrupted.
417 * The former case means there is a bug -
418 * switch to read-only mode just in case.
419 * The latter case means a real corruption - we
420 * may try to recover data. FIXME: but this is
421 * not implemented.
422 */
423 if (err == UBI_IO_BAD_HDR_EBADMSG ||
424 err == UBI_IO_BAD_HDR) {
425 ubi_warn("corrupted VID header at PEB %d, LEB %d:%d",
426 pnum, vol_id, lnum);
427 err = -EBADMSG;
428 } else
429 ubi_ro_mode(ubi);
On this path we return UBI_IO_FF and UBI_IO_FF_BITFLIPS and it
eventually gets passed to ERR_PTR(). We probably dereference the bad
pointer and oops. At that point we've gone read only so it was already
a bad situation...
430 }
431 goto out_free;
432 } else if (err == UBI_IO_BITFLIPS)
433 scrub = 1;
434
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
[ Upstream commit 19371d73c9bd31a8e634ec5a80fc19fcd7714481 ] If the WL pool runs out of PEBs we schedule a fastmap write to refill it as soon as possible. Ensure that only one at a time is scheduled otherwise we might end in a fastmap write storm because writing the fastmap can schedule another write if bitflips are detected. Signed-off-by: Richard Weinberger <richard@nod.at> Reviewed-by: Tanya Brokhman <tlinder@codeaurora.org> Reviewed-by: Guido Martínez <guido@vanguardiasur.com.ar> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
[ Upstream commit f0f393877c71ad227d36705d61d1e4062bc29cf5 ]
Commit ff1e22e7a638 ("xen/events: Mask a moving irq") open-coded
irq_move_irq() but left out checking if the IRQ is disabled. This broke
resuming from suspend since it tries to move a (disabled) irq without
holding the IRQ's desc->lock. Fix it by adding in a check for disabled
IRQs.
The resulting stacktrace was:
kernel BUG at /build/linux-UbQGH5/linux-4.4.0/kernel/irq/migration.c:31!
invalid opcode: 0000 [#1] SMP
Modules linked in: xenfs xen_privcmd ...
CPU: 0 PID: 9 Comm: migration/0 Not tainted 4.4.0-22-generic #39-Ubuntu
Hardware name: Xen HVM domU, BIOS 4.6.1-xs125180 05/04/2016
task: ffff88003d75ee00 ti: ffff88003d7bc000 task.ti: ffff88003d7bc000
RIP: 0010:[<ffffffff810e26e2>] [<ffffffff810e26e2>] irq_move_masked_irq+0xd2/0xe0
RSP: 0018:ffff88003d7bfc50 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffff88003d40ba00 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000100 RDI: ffff88003d40bad8
RBP: ffff88003d7bfc68 R08: 0000000000000000 R09: ffff88003d000000
R10: 0000000000000000 R11: 000000000000023c R12: ffff88003d40bad0
R13: ffffffff81f3a4a0 R14: 0000000000000010 R15: 00000000ffffffff
FS: 0000000000000000(0000) GS:ffff88003da00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd4264de624 CR3: 0000000037922000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
ffff88003d40ba38 0000000000000024 0000000000000000 ffff88003d7bfca0
ffffffff814c8d92 00000010813ef89d 00000000805ea732 0000000000000009
0000000000000024 ffff88003cc39b80 ffff88003d7bfce0 ffffffff814c8f66
Call Trace:
[<ffffffff814c8d92>] eoi_pirq+0xb2/0xf0
[<ffffffff814c8f66>] __startup_pirq+0xe6/0x150
[<ffffffff814ca659>] xen_irq_resume+0x319/0x360
[<ffffffff814c7e75>] xen_suspend+0xb5/0x180
[<ffffffff81120155>] multi_cpu_stop+0xb5/0xe0
[<ffffffff811200a0>] ? cpu_stop_queue_work+0x80/0x80
[<ffffffff811203d0>] cpu_stopper_thread+0xb0/0x140
[<ffffffff810a94e6>] ? finish_task_switch+0x76/0x220
[<ffffffff810ca731>] ? __raw_callee_save___pv_queued_spin_unlock+0x11/0x20
[<ffffffff810a3935>] smpboot_thread_fn+0x105/0x160
[<ffffffff810a3830>] ? sort_range+0x30/0x30
[<ffffffff810a0588>] kthread+0xd8/0xf0
[<ffffffff810a04b0>] ? kthread_create_on_node+0x1e0/0x1e0
[<ffffffff8182568f>] ret_from_fork+0x3f/0x70
[<ffffffff810a04b0>] ? kthread_create_on_node+0x1e0/0x1e0
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
[ Upstream commit 702f926067d2a4b28c10a3c41a1172dd62d9e735 ] b4ff8389ed14 is incomplete: relies on nr_legacy_irqs() to get the number of legacy interrupts when actually nr_legacy_irqs() returns 0 after probe_8259A(). Use NR_IRQS_LEGACY instead. Signed-off-by: Stefano Stabellini <sstabellini@kernel.org> CC: stable@vger.kernel.org Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
[ Upstream commit 8abb850a03a3a8b11a0e92949e5b99d9cc178e35 ] Xen overrides __acpi_register_gsi and leaves __acpi_unregister_gsi as is. That means, an IRQ allocated by acpi_register_gsi_xen_hvm() or acpi_register_gsi_xen() will be freed by acpi_unregister_gsi_ioapic(), which may cause undesired effects. So override __acpi_unregister_gsi to NULL for safety. Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Tested-by: Sander Eikelenboom <linux@eikelenboom.it> Cc: Tony Luck <tony.luck@intel.com> Cc: xen-devel@lists.xenproject.org Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Graeme Gregory <graeme.gregory@linaro.org> Cc: Lv Zheng <lv.zheng@intel.com> Link: http://lkml.kernel.org/r/1421720467-7709-4-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
[ Upstream commit bf959931ddb88c4e4366e96dd22e68fa0db9527c ]
The following program (simplified version of generated by syzkaller)
#include <pthread.h>
#include <unistd.h>
#include <sys/ptrace.h>
#include <stdio.h>
#include <signal.h>
void *thread_func(void *arg)
{
ptrace(PTRACE_TRACEME, 0,0,0);
return 0;
}
int main(void)
{
pthread_t thread;
if (fork())
return 0;
while (getppid() != 1)
;
pthread_create(&thread, NULL, thread_func, NULL);
pthread_join(thread, NULL);
return 0;
}
creates an unreapable zombie if /sbin/init doesn't use __WALL.
This is not a kernel bug, at least in a sense that everything works as
expected: debugger should reap a traced sub-thread before it can reap the
leader, but without __WALL/__WCLONE do_wait() ignores sub-threads.
Unfortunately, it seems that /sbin/init in most (all?) distributions
doesn't use it and we have to change the kernel to avoid the problem.
Note also that most init's use sys_waitid() which doesn't allow __WALL, so
the necessary user-space fix is not that trivial.
This patch just adds the "ptrace" check into eligible_child(). To some
degree this matches the "tsk->ptrace" in exit_notify(), ->exit_signal is
mostly ignored when the tracee reports to debugger. Or WSTOPPED, the
tracer doesn't need to set this flag to wait for the stopped tracee.
This obviously means the user-visible change: __WCLONE and __WALL no
longer have any meaning for debugger. And I can only hope that this won't
break something, but at least strace/gdb won't suffer.
We could make a more conservative change. Say, we can take __WCLONE into
account, or !thread_group_leader(). But it would be nice to not
complicate these historical/confusing checks.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Jan Kratochvil <jan.kratochvil@redhat.com>
Cc: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: <syzkaller@googlegroups.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>