The basic memory-mapped GPIO controller lock must be released
before calling the registered GPIO interrupt handlers to allow
the interrupt handlers to access the hardware.
Examples of why a GPIO interrupt handler might want to access
the GPIO hardware include an interrupt that is configured to
trigger on rising and falling edges that needs to read the
current level of the input to know how to respond, or an
interrupt that causes a change in a GPIO output in the same
bank. If the lock is not released before enterring the handler
the hardware accesses will deadlock when they attempt to grab
the lock.
Since the lock is only needed to protect the calculation of
unmasked pending interrupts create a dedicated function to
perform this and hide the complexity.
When nvmet_req_init() fails, __nvmet_req_complete() is called
to handle the target request via .queue_response(), so
nvme_loop_queue_response() shouldn't be called again for
handling the failure.
This patch fixes this case by the following way:
- move blk_mq_start_request() before nvmet_req_init(), so
nvme_loop_queue_response() may work well to complete this
host request
- don't call nvme_cleanup_cmd() which is done in nvme_loop_complete_rq()
- don't call nvme_loop_queue_response() which is done via
.queue_response()
Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
[trimmed changelog] Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch, basically, reverts commit 6b97a20d3a79 ("printk:
set may_schedule for some of console_trylock() callers").
That commit was a mistake, it introduced a big dependency
on the scheduler, by enabling preemption under console_sem
in printk()->console_unlock() path, which is rather too
critical. The patch did not significantly reduce the
possibilities of printk() lockups, but made it possible to
stall printk(), as has been reported by Tetsuo Handa [1].
Another issues is that preemption under console_sem also
messes up with Steven Rostedt's hand off scheme, by making
it possible to sleep with console_sem both in console_unlock()
and in vprintk_emit(), after acquiring the console_sem
ownership (anywhere between printk_safe_exit_irqrestore() in
console_trylock_spinning() and printk_safe_enter_irqsave()
in console_unlock()). This makes hand off less likely and,
at the same time, may result in a significant amount of
pending logbuf messages. Preempted console_sem owner makes
it impossible for other CPUs to emit logbuf messages, but
does not make it impossible for other CPUs to append new
messages to the logbuf.
Reinstate the old behavior and make printk() non-preemptible.
Should any printk() lockup reports arrive they must be handled
in a different way.
[1] http://lkml.kernel.org/r/201603022101.CAH73907.OVOOMFHFFtQJSL%20()%20I-love%20!%20SAKURA%20!%20ne%20!%20jp Fixes: 6b97a20d3a79 ("printk: set may_schedule for some of console_trylock() callers") Link: http://lkml.kernel.org/r/20180116044716.GE6607@jagdpanzerIV
To: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Tejun Heo <tj@kernel.org> Cc: akpm@linux-foundation.org Cc: linux-mm@kvack.org Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Jan Kara <jack@suse.cz> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Byungchul Park <byungchul.park@lge.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: linux-kernel@vger.kernel.org Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Kaixuxia repors that it's possible to crash overlayfs by removing the
whiteout on the upper layer before creating a directory over it. This is a
reproducer:
mkdir lower upper work merge
touch lower/file
mount -t overlay overlay -olowerdir=lower,upperdir=upper,workdir=work merge
rm merge/file
ls -al merge/file
rm upper/file
ls -al merge/
mkdir merge/file
Before commencing with a vfs_rename(..., RENAME_EXCHANGE) verify that the
lookup of "upper" is positive and is a whiteout, and return ESTALE
otherwise.
xen_create_contiguous_region has now only an implementation if
CONFIG_XEN_PV is defined. However, on ARM we never set CONFIG_XEN_PV but
we do have an implementation of xen_create_contiguous_region which is
required for swiotlb-xen to work correctly (although it just sets
*dma_handle).
Ensure that the writes into the context image are completed prior to the
register mmio to trigger execution. Although previously we were assured
by the SDM that all writes are flushed before an uncached memory
transaction (our mmio write to submit the context to HW for execution),
we have empirical evidence to believe that this is not actually the
case.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108656
References: https://bugs.freedesktop.org/show_bug.cgi?id=108315
References: https://bugs.freedesktop.org/show_bug.cgi?id=106887 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Acked-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20181108081740.25615-1-chris@chris-wilson.co.uk Cc: stable@vger.kernel.org
(cherry picked from commit 987abd5c62f92ee4970b45aa077f47949974e615) Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since the flags are being used to operate on a u64 variable, they too
need to be marked as such so that the inverses are full width (and not
zero extended on 32b kernels and bdw+).
Reported-by: Sergii Romantsov <sergii.romantsov@globallogic.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: stable@vger.kernel.org Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com> Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20181102161232.17742-2-chris@chris-wilson.co.uk
(cherry picked from commit 83b466b1dc5f0b4d33f0a901e8b00197a8f3582d) Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We deinit the lpe audio device before we call
drm_atomic_helper_shutdown(), which means the platform device
may already be gone when it comes time to shut down the crtc.
As we don't know when the last reference to the platform
device gets dropped by the audio driver we can't assume that
the device and its data are still around when turning off the
crtc. Mark the platform device as gone as soon as we do the
audio deinit.
Since we need to be able to allow DPMS on->off prop changes after an MST
port has disappeared from the system, we need to be able to make sure we
can compute a config for the resulting atomic commit. Currently this is
impossible when the port has disappeared, since the VCPI slot searching
we try to do in intel_dp_mst_compute_config() will fail with -EINVAL.
Since the only commits we want to allow on no-longer-present MST ports
are ones that shut off display hardware, we already know that no VCPI
allocations are needed. So, hardcode the VCPI slot count to 0 when
intel_dp_mst_compute_config() is called on an MST port that's gone.
Changes since V4:
- Don't use mst_port_gone at all, just check whether or not the drm
connector is registered - Daniel Vetter
Currently we set intel_connector->mst_port to NULL to signify that the
MST port has been removed from the system so that we can prevent further
action on the port such as connector probes, mode probing, etc.
However, we're going to need access to intel_connector->mst_port in
order to fixup ->best_encoder() so that it can always return the correct
encoder for an MST port to prevent legacy DPMS prop changes from
failing. This should be safe, so instead keep intel_connector->mst_port
always set and instead just check the status of
drm_connector->regustered to signify whether or not the connector has
disappeared from the system.
Changes since v2:
- Add a comment to mst_port_gone (Jani Nikula)
- Change mst_port_gone to a u8 instead of a bool, per the kernel bot.
Apparently bool is discouraged in structs these days
Changes since v4:
- Don't use mst_port_gone at all! Just check if the connector is
registered or not - Daniel Vetter
Unfortunately drm_dp_get_mst_branch_device which is called from both
drm_dp_mst_handle_down_rep and drm_dp_mst_handle_up_rep seem to rely
on that mgr->mst_primary is not NULL, which seem to be wrong as it can be
cleared with simultaneous mode set, if probing fails or in other case.
mgr->lock mutex doesn't protect against that as it might just get
assigned to NULL right before, not simultaneously.
There are currently bugs 107738, 108616 bugs which crash in
drm_dp_get_mst_branch_device, caused by this issue.
v2: Refactored the code, as it was nicely noticed.
Fixed Bugzilla bug numbers(second was 108616, but not 108816)
and added links.
[changed title and added stable cc] Signed-off-by: Lyude Paul <lyude@redhat.com> Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com> Cc: stable@vger.kernel.org
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108616
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=107738 Link: https://patchwork.freedesktop.org/patch/msgid/20181109090012.24438-1-stanislav.lisovskiy@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Leaving the DRM driver enabled on reboot or kexec has the annoying
effect of leaving the display generating transactions whilst the
IOMMU has been shut down.
In turn, the IOMMU driver (which shares its interrupt line with
the VOP) starts warning either on shutdown or when entering the
secondary kernel in the kexec case (nothing is expected on that
front).
A cheap way of ensuring that things are nicely shut down is to
register a shutdown callback in the platform driver.
24d7c494ce46 ("efi/arm-stub: Round up FDT allocation to mapping size")
increased the allocation size for the FDT image created by the stub to a
fixed value of 2 MB, to simplify the former code that made several
attempts with increasing values for the size. This is reasonable
given that the allocation is of type EFI_LOADER_DATA, which is released
to the kernel unless it is explicitly memblock_reserve()d by the early
boot code.
However, this allocation size leaked into the 'size' field of the FDT
header metadata, and so the entire allocation remains occupied by the
device tree binary, even if most of it is not used to store device tree
information.
So call fdt_pack() to shrink the FDT data structure to its minimum size
after populating all the fields, so that the remaining memory is no
longer wasted.
Commit a2468cc9bfdf ("swap: choose swap device according to numa node")
changed 'avail_lists' field of 'struct swap_info_struct' to an array.
In popular linux distros it increased size of swap_info_struct up to 40
Kbytes and now swap_info_struct allocation requires order-4 page.
Switch to kvzmalloc allows to avoid unexpected allocation failures.
Link: http://lkml.kernel.org/r/fc23172d-3c75-21e2-d551-8b1808cbe593@virtuozzo.com Fixes: a2468cc9bfdf ("swap: choose swap device according to numa node") Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Acked-by: Aaron Lu <aaron.lu@intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Huang Ying <ying.huang@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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This bug has been experienced several times by the Oracle DB team. The
BUG is in remove_inode_hugepages() as follows:
/*
* If page is mapped, it was faulted in after being
* unmapped in caller. Unmap (again) now after taking
* the fault mutex. The mutex will prevent faults
* until we finish removing the page.
*
* This race can only happen in the hole punch case.
* Getting here in a truncate operation is a bug.
*/
if (unlikely(page_mapped(page))) {
BUG_ON(truncate_op);
In this case, the elevated map count is not the result of a race.
Rather it was incorrectly incremented as the result of a bug in the huge
pmd sharing code. Consider the following:
- Process A maps a hugetlbfs file of sufficient size and alignment
(PUD_SIZE) that a pmd page could be shared.
- Process B maps the same hugetlbfs file with the same size and
alignment such that a pmd page is shared.
- Process B then calls mprotect() to change protections for the mapping
with the shared pmd. As a result, the pmd is 'unshared'.
- Process B then calls mprotect() again to chage protections for the
mapping back to their original value. pmd remains unshared.
- Process B then forks and process C is created. During the fork
process, we do dup_mm -> dup_mmap -> copy_page_range to copy page
tables. Copying page tables for hugetlb mappings is done in the
routine copy_hugetlb_page_range.
In copy_hugetlb_page_range(), the destination pte is obtained by:
dst_pte = huge_pte_alloc(dst, addr, sz);
If pmd sharing is possible, the returned pointer will be to a pte in an
existing page table. In the situation above, process C could share with
either process A or process B. Since process A is first in the list,
the returned pte is a pointer to a pte in process A's page table.
However, the check for pmd sharing in copy_hugetlb_page_range is:
/* If the pagetables are shared don't copy or take references */
if (dst_pte == src_pte)
continue;
Since process C is sharing with process A instead of process B, the
above test fails. The code in copy_hugetlb_page_range which follows
assumes dst_pte points to a huge_pte_none pte. It copies the pte entry
from src_pte to dst_pte and increments this map count of the associated
page. This is how we end up with an elevated map count.
To solve, check the dst_pte entry for huge_pte_none. If !none, this
implies PMD sharing so do not copy.
Link: http://lkml.kernel.org/r/20181105212315.14125-1-mike.kravetz@oracle.com Fixes: c5c99429fa57 ("fix hugepages leak due to pagetable page sharing") Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Hugh Dickins <hughd@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Prakash Sangappa <prakash.sangappa@oracle.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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gcc-8 complains about the prototype for this function:
lib/ubsan.c:432:1: error: ignoring attribute 'noreturn' in declaration of a built-in function '__ubsan_handle_builtin_unreachable' because it conflicts with attribute 'const' [-Werror=attributes]
This is actually a GCC's bug. In GCC internals
__ubsan_handle_builtin_unreachable() declared with both 'noreturn' and
'const' attributes instead of only 'noreturn':
All bytes of the NETLINK_CRYPTO report structures must be initialized,
since they are copied to userspace. The change from strncpy() to
strlcpy() broke this. As a minimal fix, change it back.
Fixes: 4473710df1f8 ("crypto: user - Prepare for CRYPTO_MAX_ALG_NAME expansion") Cc: <stable@vger.kernel.org> # v4.12+ Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gfs2_put_super calls gfs2_clear_rgrpd to destroy the gfs2_rgrpd objects
attached to the resource group glocks. That function should release the
buffers attached to the gfs2_bitmap objects (bi_bh), but the call to
gfs2_rgrp_brelse for doing that is missing.
When gfs2_releasepage later runs across these buffers which are still
referenced, it refuses to free them. This causes the pages the buffers
are attached to to remain referenced as well. With enough mount/unmount
cycles, the system will eventually run out of memory.
Fix this by adding the missing call to gfs2_rgrp_brelse in
gfs2_clear_rgrpd.
(Also fix a gfs2_rgrp_relse -> gfs2_rgrp_brelse typo in a comment.)
fs/configfs/symlink.c:67:3: warning:
'strncpy' output truncated before terminating nul copying as many
bytes from a string as its length
fs/configfs/symlink.c: In function 'configfs_get_link':
fs/configfs/symlink.c:63:13: note: length computed here
Using strncpy() is indeed less than perfect since the length of data to
be copied has already been determined with strlen(). Replace strncpy()
with memcpy() to address the warning and optimize the code a little.
fuse_request_send_notify_reply() may fail if the connection was reset for
some reason (e.g. fs was unmounted). Don't leak request reference in this
case. Besides leaking memory, this resulted in fc->num_waiting not being
decremented and hence fuse_wait_aborted() left in a hanging and unkillable
state.
Fixes: 2d45ba381a74 ("fuse: add retrieve request") Fixes: b8f95e5d13f5 ("fuse: umount should wait for all requests") Reported-and-tested-by: syzbot+6339eda9cb4ebbc4c37b@syzkaller.appspotmail.com Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Cc: <stable@vger.kernel.org> #v2.6.36 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In async IO blocking case the additional reference to the io is taken for
it to survive fuse_aio_complete(). In non blocking case this additional
reference is not needed, however we still reference io to figure out
whether to wait for completion or not. This is wrong and will lead to
use-after-free. Fix it by storing blocking information in separate
variable.
This was spotted by KASAN when running generic/208 fstest.
Fix an issue with the 32-bit range error path in `rtc_hctosys' where no
error code is set and consequently the successful preceding call result
from `rtc_read_time' is propagated to `rtc_hctosys_ret'. This in turn
makes any subsequent call to `hctosys_show' incorrectly report in sysfs
that the system time has been set from this RTC while it has not.
Set the error to ERANGE then if we can't express the result due to an
overflow.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Fixes: b3a5ac42ab18 ("rtc: hctosys: Ensure system time doesn't overflow time_t") Cc: stable@vger.kernel.org # 4.17+ Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make sure we have a saved filehandle, otherwise we'll oops with a null
pointer dereference in nfs4_preprocess_stateid_op().
Signed-off-by: Scott Mayhew <smayhew@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When truncating the encode buffer, the page_ptr is getting
advanced, causing the next page to be skipped while encoding.
The page is still included in the response, so the response
contains a page of bogus data.
We need to adjust the page_ptr backwards to ensure we encode
the next page into the correct place.
We saw this triggered when concurrent directory modifications caused
nfsd4_encode_direct_fattr() to return nfserr_noent, and the resulting
call to xdr_truncate_encode() corrupted the READDIR reply.
Signed-off-by: Frank Sorenson <sorenson@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since commit ad67b74d2469 ("printk: hash addresses printed with %p"),
all pointers printed with %p are printed with hashed addresses
instead of real addresses in order to avoid leaking addresses in
dmesg and syslog. But this applies to kdb too, with is unfortunate:
Entering kdb (current=0x(ptrval), pid 329) due to Keyboard Entry
kdb> ps
15 sleeping system daemon (state M) processes suppressed,
use 'ps A' to see all.
Task Addr Pid Parent [*] cpu State Thread Command
0x(ptrval) 329 328 1 0 R 0x(ptrval) *sh
0x(ptrval) 1 0 0 0 S 0x(ptrval) init
0x(ptrval) 3 2 0 0 D 0x(ptrval) rcu_gp
0x(ptrval) 4 2 0 0 D 0x(ptrval) rcu_par_gp
0x(ptrval) 5 2 0 0 D 0x(ptrval) kworker/0:0
0x(ptrval) 6 2 0 0 D 0x(ptrval) kworker/0:0H
0x(ptrval) 7 2 0 0 D 0x(ptrval) kworker/u2:0
0x(ptrval) 8 2 0 0 D 0x(ptrval) mm_percpu_wq
0x(ptrval) 10 2 0 0 D 0x(ptrval) rcu_preempt
The whole purpose of kdb is to debug, and for debugging real addresses
need to be known. In addition, data displayed by kdb doesn't go into
dmesg.
This patch replaces all %p by %px in kdb in order to display real
addresses.
Entering kdb (current=0x(ptrval), pid 282) due to Keyboard Entry
kdb> btc
btc: cpu status: Currently on cpu 0
Available cpus: 0
kdb_getarea: Bad address 0x0
when booting the kernel with 'debug_boot_weak_hash', it fails as well
Entering kdb (current=0xba99ad80, pid 284) due to Keyboard Entry
kdb> btc
btc: cpu status: Currently on cpu 0
Available cpus: 0
kdb_getarea: Bad address 0xba99ad80
On other platforms, Oopses have been observed too, see
https://github.com/linuxppc/linux/issues/139
This is due to btc calling 'btt' with %p pointer as an argument.
This patch replaces %p by %px to get the real pointer value as
expected by 'btt'
Fixes: ad67b74d2469 ("printk: hash addresses printed with %p") Cc: <stable@vger.kernel.org> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Timothy Baldwin <timbaldwin@fastmail.co.uk> wrote:
> As per mount_namespaces(7) unprivileged users should not be able to look under mount points:
>
> Mounts that come as a single unit from more privileged mount are locked
> together and may not be separated in a less privileged mount namespace.
>
> However they can:
>
> 1. Create a mount namespace.
> 2. In the mount namespace open a file descriptor to the parent of a mount point.
> 3. Destroy the mount namespace.
> 4. Use the file descriptor to look under the mount point.
>
> I have reproduced this with Linux 4.16.18 and Linux 4.18-rc8.
>
> The setup:
>
> $ sudo sysctl kernel.unprivileged_userns_clone=1
> kernel.unprivileged_userns_clone = 1
> $ mkdir -p A/B/Secret
> $ sudo mount -t tmpfs hide A/B
>
>
> "Secret" is indeed hidden as expected:
>
> $ ls -lR A
> A:
> total 0
> drwxrwxrwt 2 root root 40 Feb 12 21:08 B
>
> A/B:
> total 0
>
>
> The attack revealing "Secret":
>
> $ unshare -Umr sh -c "exec unshare -m ls -lR /proc/self/fd/4/ 4<A"
> /proc/self/fd/4/:
> total 0
> drwxr-xr-x 3 root root 60 Feb 12 21:08 B
>
> /proc/self/fd/4/B:
> total 0
> drwxr-xr-x 2 root root 40 Feb 12 21:08 Secret
>
> /proc/self/fd/4/B/Secret:
> total 0
I tracked this down to put_mnt_ns running passing UMOUNT_SYNC and
disconnecting all of the mounts in a mount namespace. Fix this by
factoring drop_mounts out of drop_collected_mounts and passing
0 instead of UMOUNT_SYNC.
There are two possible behavior differences that result from this.
- No longer setting UMOUNT_SYNC will no longer set MNT_SYNC_UMOUNT on
the vfsmounts being unmounted. This effects the lazy rcu walk by
kicking the walk out of rcu mode and forcing it to be a non-lazy
walk.
- No longer disconnecting locked mounts will keep some mounts around
longer as they stay because the are locked to other mounts.
There are only two users of drop_collected mounts: audit_tree.c and
put_mnt_ns.
In audit_tree.c the mounts are private and there are no rcu lazy walks
only calls to iterate_mounts. So the changes should have no effect
except for a small timing effect as the connected mounts are disconnected.
In put_mnt_ns there may be references from process outside the mount
namespace to the mounts. So the mounts remaining connected will
be the bug fix that is needed. That rcu walks are allowed to continue
appears not to be a problem especially as the rcu walk change was about
an implementation detail not about semantics.
Cc: stable@vger.kernel.org Fixes: 5ff9d8a65ce8 ("vfs: Lock in place mounts from more privileged users") Reported-by: Timothy Baldwin <timbaldwin@fastmail.co.uk> Tested-by: Timothy Baldwin <timbaldwin@fastmail.co.uk> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Jonathan Calmels from NVIDIA reported that he's able to bypass the
mount visibility security check in place in the Linux kernel by using
a combination of the unbindable property along with the private mount
propagation option to allow a unprivileged user to see a path which
was purposefully hidden by the root user.
Reproducer:
# Hide a path to all users using a tmpfs
root@castiana:~# mount -t tmpfs tmpfs /sys/devices/
root@castiana:~#
# As an unprivileged user, unshare user namespace and mount namespace
stgraber@castiana:~$ unshare -U -m -r
# Confirm the path is still not accessible
root@castiana:~# ls /sys/devices/
# Make /sys recursively unbindable and private
root@castiana:~# mount --make-runbindable /sys
root@castiana:~# mount --make-private /sys
# Recursively bind-mount the rest of /sys over to /mnnt
root@castiana:~# mount --rbind /sys/ /mnt
# Access our hidden /sys/device as an unprivileged user
root@castiana:~# ls /mnt/devices/
breakpoint cpu cstate_core cstate_pkg i915 intel_pt isa kprobe
LNXSYSTM:00 msr pci0000:00 platform pnp0 power software system
tracepoint uncore_arb uncore_cbox_0 uncore_cbox_1 uprobe virtual
Solve this by teaching copy_tree to fail if a mount turns out to be
both unbindable and locked.
Cc: stable@vger.kernel.org Fixes: 5ff9d8a65ce8 ("vfs: Lock in place mounts from more privileged users") Reported-by: Jonathan Calmels <jcalmels@nvidia.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It was recently pointed out that the one instance of testing MNT_LOCKED
outside of the namespace_sem is in ksys_umount.
Fix that by adding a test inside of do_umount with namespace_sem and
the mount_lock held. As it helps to fail fails the existing test is
maintained with an additional comment pointing out that it may be racy
because the locks are not held.
Cc: stable@vger.kernel.org Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Fixes: 5ff9d8a65ce8 ("vfs: Lock in place mounts from more privileged users") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
According to Ted Ts'o ext4_getblk() called in ext4_xattr_inode_write()
should not return bh = NULL
The only time that bh could be NULL, then, would be in the case of
something really going wrong; a programming error elsewhere (perhaps a
wild pointer dereference) or I/O error causing on-disk file system
corruption (although that would be highly unlikely given that we had
*just* allocated the blocks and so the metadata blocks in question
probably would still be in the cache).
Currently bh is set to NULL only during first iteration of for cycle,
then this pointer is not cleared after end of using.
Therefore rollback after errors can lead to extra brelse(bh) call,
decrements bh counter and later trigger an unexpected warning in __brelse()
Patch moves brelse() calls in body of cycle to exclude requirement of
brelse() call in rollback.
Fixes: 33afdcc5402d ("ext4: add a function which sets up group blocks ...") Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org # 3.3+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for platforms where pit_shutdown() doesn't work because of a
quirk in the PIT emulation. On these platforms setting the counter register
to zero causes the PIT to start running again, negating the shutdown.
Provide a global variable that controls whether the counter register is
zero'ed, which platform specific code can override.
We currently allow cloning a range from a file which includes the last
block of the file even if the file's size is not aligned to the block
size. This is fine and useful when the destination file has the same size,
but when it does not and the range ends somewhere in the middle of the
destination file, it leads to corruption because the bytes between the EOF
and the end of the block have undefined data (when there is support for
discard/trimming they have a value of 0x00).
The bytes in the range from 786532 (512Kb + 256Kb + 100 bytes) to 790527
(512Kb + 256Kb + 4Kb - 1) got corrupted, having now a value of 0x00 instead
of 0xb5.
This is similar to the problem we had for deduplication that got recently
fixed by commit de02b9f6bb65 ("Btrfs: fix data corruption when
deduplicating between different files").
Fix this by not allowing such operations to be performed and return the
errno -EINVAL to user space. This is what XFS is doing as well at the VFS
level. This change however now makes us return -EINVAL instead of
-EOPNOTSUPP for cases where the source range maps to an inline extent and
the destination range's end is smaller then the destination file's size,
since the detection of inline extents is done during the actual process of
dropping file extent items (at __btrfs_drop_extents()). Returning the
-EINVAL error is done early on and solely based on the input parameters
(offsets and length) and destination file's size. This makes us consistent
with XFS and anyone else supporting cloning since this case is now checked
at a higher level in the VFS and is where the -EINVAL will be returned
from starting with kernel 4.20 (the VFS changed was introduced in 4.20-rc1
by commit 07d19dc9fbe9 ("vfs: avoid problematic remapping requests into
partial EOF block"). So this change is more geared towards stable kernels,
as it's unlikely the new VFS checks get removed intentionally.
A test case for fstests follows soon, as well as an update to filter
existing tests that expect -EOPNOTSUPP to accept -EINVAL as well.
CC: <stable@vger.kernel.org> # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If we attempt to deduplicate the last block of a file A into the middle of
a file B, and file A's size is not a multiple of the block size, we end
rounding the deduplication length to 0 bytes, to avoid the data corruption
issue fixed by commit de02b9f6bb65 ("Btrfs: fix data corruption when
deduplicating between different files"). However a length of zero will
cause the insertion of an extent state with a start value greater (by 1)
then the end value, leading to a corrupt extent state that will trigger a
warning and cause chaos such as an infinite loop during inode eviction.
Example trace:
The second stack trace, from inode eviction, is repeated forever due to
the infinite loop during eviction.
This is the same type of problem fixed way back in 2015 by commit 113e8283869b ("Btrfs: fix inode eviction infinite loop after extent_same
ioctl") and commit ccccf3d67294 ("Btrfs: fix inode eviction infinite loop
after cloning into it").
So fix this by returning immediately if the deduplication range length
gets rounded down to 0 bytes, as there is nothing that needs to be done in
such case.
# Unmount the filesystem and mount it again so that we start without any
# extent state records when we ask for the deduplication.
$ umount /mnt
$ mount /dev/sdb /mnt
$ xfs_io -c "dedupe /mnt/foo 0 500K 100" /mnt/bar
# This unmount triggers the infinite loop.
$ umount /mnt
A test case for fstests will follow soon.
Fixes: de02b9f6bb65 ("Btrfs: fix data corruption when deduplicating between different files") CC: <stable@vger.kernel.org> # 4.19+ Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the cow_file_range fails, the related resources are unlocked
according to the range [start..end), so the unlock cannot be repeated in
run_delalloc_nocow.
In some cases (e.g. cur_offset <= end && cow_start != -1), cur_offset is
not updated correctly, so move the cur_offset update before
cow_file_range.
In the above line there's "pinned=18446744073708158976" which is an
unsigned u64 value of -1392640, an obvious underflow.
When transaction_kthread is running cleanup_transaction(), another
fsstress is running btrfs_commit_transaction(). The
btrfs_finish_extent_commit() may get the same range as
btrfs_destroy_pinned_extent() got, which causes the pinned underflow.
Fixes: d4b450cd4b33 ("Btrfs: fix race between transaction commit and empty block group removal") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The split out of the hard lockup detector exposed two new weak functions,
but no prototypes for them, which triggers the build warning:
kernel/watchdog.c:109:12: warning: no previous prototype for ‘watchdog_nmi_enable’ [-Wmissing-prototypes]
kernel/watchdog.c:115:13: warning: no previous prototype for ‘watchdog_nmi_disable’ [-Wmissing-prototypes]
Add the prototypes.
Fixes: 73ce0511c436 ("kernel/watchdog.c: move hardlockup detector to separate file") Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Babu Moger <babu.moger@oracle.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180606194232.17653-1-malat@debian.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Alpha has had c_ispeed and c_ospeed, but still set speeds in c_cflags
using arbitrary flags. Because BOTHER is not defined, the general
Linux code doesn't allow setting arbitrary baud rates, and because
CBAUDEX == 0, we can have an array overrun of the baud_rate[] table in
drivers/tty/tty_baudrate.c if (c_cflags & CBAUD) == 037.
Resolve both problems by #defining BOTHER to 037 on Alpha.
However, userspace still needs to know if setting BOTHER is actually
safe given legacy kernels (does anyone actually care about that on
Alpha anymore?), so enable the TCGETS2/TCSETS*2 ioctls on Alpha, even
though they use the same structure. Define struct termios2 just for
compatibility; it is the exact same structure as struct termios. In a
future patchset, this will be cleaned up so the uapi headers are
usable from libc.
Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Eugene Syromiatnikov <esyr@redhat.com> Cc: <linux-alpha@vger.kernel.org> Cc: <linux-serial@vger.kernel.org> Cc: Johan Hovold <johan@kernel.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On architectures with CBAUDEX == 0 (Alpha and PowerPC), the code in tty_baudrate.c does
not do any limit checking on the tty_baudrate[] array, and in fact a
buffer overrun is possible on both architectures. Add a limit check to
prevent that situation.
This will be followed by a much bigger cleanup/simplification patch.
Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com> Requested-by: Cc: Johan Hovold <johan@kernel.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Eugene Syromiatnikov <esyr@redhat.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Hyper-V emulation of the PIT has a quirk such that the normal PIT shutdown
path doesn't work, because clearing the counter register restarts the
timer.
When running function tracing on a Linux guest running on VMware
Workstation, the guest would crash. This is due to tracing of the
sched_clock internal call of the VMware vmware_sched_clock(), which
causes an infinite recursion within the tracing code (clock calls must
not be traced).
Currently the NUMA distance map parsing does not validate the distance
table for the distance-matrix rules 1-2 in [1].
However the arch NUMA code may enforce some of these rules, but not all.
Such is the case for the arm64 port, which does not enforce the rule that
the distance between separates nodes cannot equal LOCAL_DISTANCE.
The patch adds the following rules validation:
- distance of node to self equals LOCAL_DISTANCE
- distance of separate nodes > LOCAL_DISTANCE
This change avoids a yet-unresolved crash reported in [2].
A note on dealing with symmetrical distances between nodes:
Validating symmetrical distances between nodes is difficult. If it were
mandated in the bindings that every distance must be recorded in the
table, then it would be easy. However, it isn't.
In addition to this, it is also possible to record [b, a] distance only
(and not [a, b]). So, when processing the table for [b, a], we cannot
assert that current distance of [a, b] != [b, a] as invalid, as [a, b]
distance may not be present in the table and current distance would be
default at REMOTE_DISTANCE.
As such, we maintain the policy that we overwrite distance [a, b] = [b, a]
for b > a. This policy is different to kernel ACPI SLIT validation, which
allows non-symmetrical distances (ACPI spec SLIT rules allow it). However,
the distance debug message is dropped as it may be misleading (for a distance
which is later overwritten).
Some final notes on semantics:
- It is implied that it is the responsibility of the arch NUMA code to
reset the NUMA distance map for an error in distance map parsing.
- It is the responsibility of the FW NUMA topology parsing (whether OF or
ACPI) to enforce NUMA distance rules, and not arch NUMA code.
I noticed during the creation of another bugfix that the BCH_CONST_PARAMS
option that is set by DOCG3 breaks setting variable parameters for any
other users of the BCH library code.
The only other user we have today is the MTD_NAND software BCH
implementation (most flash controllers use hardware BCH these days
and are not affected). I considered removing BCH_CONST_PARAMS entirely
because of the inherent conflict, but according to the description in
lib/bch.c there is a significant performance benefit in keeping it.
To avoid the immediate problem of the conflict between MTD_NAND_BCH
and DOCG3, this only sets the constant parameters if MTD_NAND_BCH
is disabled, which should fix the problem for all cases that
are affected. This should also work for all stable kernels.
Note that there is only one machine that actually seems to use the
DOCG3 driver (arch/arm/mach-pxa/mioa701.c), so most users should have
the driver disabled, but it almost certainly shows up if we wanted
to test random kernels on machines that use software BCH in MTD.
Due to what appears to be a copy/paste error, the opening ENTRY()
of cpu_v7_hvc_switch_mm() lacks a matching ENDPROC(), and instead,
the one for cpu_v7_smc_switch_mm() is duplicated.
Given that it is ENDPROC() that emits the Thumb annotation, the
cpu_v7_hvc_switch_mm() routine will be called in ARM mode on a
Thumb2 kernel, resulting in the following splat:
Cc: <stable@vger.kernel.org> Fixes: 10115105cb3a ("ARM: spectre-v2: add firmware based hardening") Reviewed-by: Dave Martin <Dave.Martin@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If there's no entry to drop in bucket that corresponds to the hash,
early_drop() should look for it in other buckets. But since it increments
hash instead of bucket number, it actually looks in the same bucket 8
times: hsize is 16k by default (14 bits) and hash is 32-bit value, so
reciprocal_scale(hash, hsize) returns the same value for hash..hash+7 in
most cases.
Fix it by increasing bucket number instead of hash and rename _hash
to bucket to avoid future confusion.
THP allocation might be really disruptive when allocated on NUMA system
with the local node full or hard to reclaim. Stefan has posted an
allocation stall report on 4.12 based SLES kernel which suggests the
same issue:
The defrag mode is "madvise" and from the above report it is clear that
the THP has been allocated for MADV_HUGEPAGA vma.
Andrea has identified that the main source of the problem is
__GFP_THISNODE usage:
: The problem is that direct compaction combined with the NUMA
: __GFP_THISNODE logic in mempolicy.c is telling reclaim to swap very
: hard the local node, instead of failing the allocation if there's no
: THP available in the local node.
:
: Such logic was ok until __GFP_THISNODE was added to the THP allocation
: path even with MPOL_DEFAULT.
:
: The idea behind the __GFP_THISNODE addition, is that it is better to
: provide local memory in PAGE_SIZE units than to use remote NUMA THP
: backed memory. That largely depends on the remote latency though, on
: threadrippers for example the overhead is relatively low in my
: experience.
:
: The combination of __GFP_THISNODE and __GFP_DIRECT_RECLAIM results in
: extremely slow qemu startup with vfio, if the VM is larger than the
: size of one host NUMA node. This is because it will try very hard to
: unsuccessfully swapout get_user_pages pinned pages as result of the
: __GFP_THISNODE being set, instead of falling back to PAGE_SIZE
: allocations and instead of trying to allocate THP on other nodes (it
: would be even worse without vfio type1 GUP pins of course, except it'd
: be swapping heavily instead).
Fix this by removing __GFP_THISNODE for THP requests which are
requesting the direct reclaim. This effectivelly reverts 5265047ac301
on the grounds that the zone/node reclaim was known to be disruptive due
to premature reclaim when there was memory free. While it made sense at
the time for HPC workloads without NUMA awareness on rare machines, it
was ultimately harmful in the majority of cases. The existing behaviour
is similar, if not as widespare as it applies to a corner case but
crucially, it cannot be tuned around like zone_reclaim_mode can. The
default behaviour should always be to cause the least harm for the
common case.
If there are specialised use cases out there that want zone_reclaim_mode
in specific cases, then it can be built on top. Longterm we should
consider a memory policy which allows for the node reclaim like behavior
for the specific memory ranges which would allow a
: Both patches look correct to me but I'm responding to this one because
: it's the fix. The change makes sense and moves further away from the
: severe stalling behaviour we used to see with both THP and zone reclaim
: mode.
:
: I put together a basic experiment with usemem configured to reference a
: buffer multiple times that is 80% the size of main memory on a 2-socket
: box with symmetric node sizes and defrag set to "always". The defrag
: setting is not the default but it would be functionally similar to
: accessing a buffer with madvise(MADV_HUGEPAGE). Usemem is configured to
: reference the buffer multiple times and while it's not an interesting
: workload, it would be expected to complete reasonably quickly as it fits
: within memory. The results were;
:
: usemem
: vanilla noreclaim-v1
: Amean Elapsd-1 42.78 ( 0.00%) 26.87 ( 37.18%)
: Amean Elapsd-3 27.55 ( 0.00%) 7.44 ( 73.00%)
: Amean Elapsd-4 5.72 ( 0.00%) 5.69 ( 0.45%)
:
: This shows the elapsed time in seconds for 1 thread, 3 threads and 4
: threads referencing buffers 80% the size of memory. With the patches
: applied, it's 37.18% faster for the single thread and 73% faster with two
: threads. Note that 4 threads showing little difference does not indicate
: the problem is related to thread counts. It's simply the case that 4
: threads gets spread so their workload mostly fits in one node.
:
: The overall view from /proc/vmstats is more startling
:
: 4.19.0-rc1 4.19.0-rc1
: vanillanoreclaim-v1r1
: Minor Faults 35593425 708164
: Major Faults 484088 36
: Swap Ins 3772837 0
: Swap Outs 3932295 0
:
: Massive amounts of swap in/out without the patch
:
: Direct pages scanned 6013214 0
: Kswapd pages scanned 0 0
: Kswapd pages reclaimed 0 0
: Direct pages reclaimed 4033009 0
:
: Lots of reclaim activity without the patch
:
: Kswapd efficiency 100% 100%
: Kswapd velocity 0.000 0.000
: Direct efficiency 67% 100%
: Direct velocity 11191.956 0.000
:
: Mostly from direct reclaim context as you'd expect without the patch.
:
: Page writes by reclaim 3932314.000 0.000
: Page writes file 19 0
: Page writes anon 3932295 0
: Page reclaim immediate 42336 0
:
: Writes from reclaim context is never good but the patch eliminates it.
:
: We should never have default behaviour to thrash the system for such a
: basic workload. If zone reclaim mode behaviour is ever desired but on a
: single task instead of a global basis then the sensible option is to build
: a mempolicy that enforces that behaviour.
This was a severe regression compared to previous kernels that made
important workloads unusable and it starts when __GFP_THISNODE was
added to THP allocations under MADV_HUGEPAGE. It is not a significant
risk to go to the previous behavior before __GFP_THISNODE was added, it
worked like that for years.
This was simply an optimization to some lucky workloads that can fit in
a single node, but it ended up breaking the VM for others that can't
possibly fit in a single node, so going back is safe.
[mhocko@suse.com: rewrote the changelog based on the one from Andrea] Link: http://lkml.kernel.org/r/20180925120326.24392-2-mhocko@kernel.org Fixes: 5265047ac301 ("mm, thp: really limit transparent hugepage allocation to local node") Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Michal Hocko <mhocko@suse.com> Reported-by: Stefan Priebe <s.priebe@profihost.ag> Debugged-by: Andrea Arcangeli <aarcange@redhat.com> Reported-by: Alex Williamson <alex.williamson@redhat.com> Reviewed-by: Mel Gorman <mgorman@techsingularity.net> Tested-by: Mel Gorman <mgorman@techsingularity.net> Cc: Zi Yan <zi.yan@cs.rutgers.edu> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: David Rientjes <rientjes@google.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: <stable@vger.kernel.org> [4.1+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The write context should also be freed even when direct IO failed.
Otherwise a memory leak is introduced and entries remain in
oi->ip_unwritten_list causing the following BUG later in unlink path:
Somehow, file system metadata was corrupted, which causes
ocfs2_check_dir_entry() to fail in function ocfs2_dir_foreach_blk_el().
According to the original design intention, if above happens we should
skip the problematic block and continue to retrieve dir entry. But
there is obviouse misuse of brelse around related code.
After failure of ocfs2_check_dir_entry(), current code just moves to
next position and uses the problematic buffer head again and again
during which the problematic buffer head is released for multiple times.
I suppose, this a serious issue which is long-lived in ocfs2. This may
cause other file systems which is also used in a the same host insane.
So we should also consider about bakcporting this patch into linux
-stable.
Link: http://lkml.kernel.org/r/HK2PR06MB045211675B43EED794E597B6D56E0@HK2PR06MB0452.apcprd06.prod.outlook.com Signed-off-by: Changwei Ge <ge.changwei@h3c.com> Suggested-by: Changkuo Shi <shi.changkuo@h3c.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joseph Qi <jiangqi903@gmail.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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Keystone QMSS driver is pretty damaged, in the sense that it
does things like this:
irq_set_affinity_hint(irq, to_cpumask(&cpu_map));
where cpu_map is a local variable. As we leave the function, this
will point to nowhere-land, and things will end-up badly.
Instead, let's use a proper cpumask that gets allocated, giving
the driver a chance to actually work with things like irqbalance
as well as have a hypothetical 64bit future.
Cc: stable@vger.kernel.org Acked-by: Santosh Shilimkar <ssantosh@kernel.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Olof Johansson <olof@lixom.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
c2856ae2f315d ("blk-mq: quiesce queue before freeing queue") has
already fixed this race, however the implied synchronize_rcu()
in blk_mq_quiesce_queue() can slow down LUN probe a lot, so caused
performance regression.
Then 1311326cf4755c7 ("blk-mq: avoid to synchronize rcu inside blk_cleanup_queue()")
tried to quiesce queue for avoiding unnecessary synchronize_rcu()
only when queue initialization is done, because it is usual to see
lots of inexistent LUNs which need to be probed.
However, turns out it isn't safe to quiesce queue only when queue
initialization is done. Because when one SCSI command is completed,
the user of sending command can be waken up immediately, then the
scsi device may be removed, meantime the run queue in scsi_end_request()
is still in-progress, so kernel panic can be caused.
In Red Hat QE lab, there are several reports about this kind of kernel
panic triggered during kernel booting.
This patch tries to address the issue by grabing one queue usage
counter during freeing one request and the following run queue.
Fixes: 1311326cf4755c7 ("blk-mq: avoid to synchronize rcu inside blk_cleanup_queue()") Cc: Andrew Jones <drjones@redhat.com> Cc: Bart Van Assche <bart.vanassche@wdc.com> Cc: linux-scsi@vger.kernel.org Cc: Martin K. Petersen <martin.petersen@oracle.com> Cc: Christoph Hellwig <hch@lst.de> Cc: James E.J. Bottomley <jejb@linux.vnet.ibm.com> Cc: stable <stable@vger.kernel.org> Cc: jianchao.wang <jianchao.w.wang@oracle.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commands with protection information included were not truncating the
protection iov_iter to the number of protection bytes in the command.
This resulted in vhost_scsi mis-calculating the size of the protection
SGL in vhost_scsi_calc_sgls(), and including both the protection and
data SG entries in the protection SGL.
Fixes: 09b13fa8c1a1 ("vhost/scsi: Add ANY_LAYOUT support in vhost_scsi_handle_vq") Signed-off-by: Greg Edwards <gedwards@ddn.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Fixes: 09b13fa8c1a1093e9458549ac8bb203a7c65c62a Cc: stable@vger.kernel.org Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a potential execution path in which function
platform_get_resource() returns NULL. If this happens,
we will end up having a NULL pointer dereference.
Fix this by replacing devm_ioremap with devm_ioremap_resource,
which has the NULL check and the memory region request.
This code was detected with the help of Coccinelle.
Cc: stable@vger.kernel.org Fixes: 97b7129cd2af ("reset: hisilicon: change the definition of hisi_reset_init") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reading the registers without waiting for engine idle returns
unpredictable values. These unpredictable values result in display
corruption - if atyfb_imageblit reads the content of DP_PIX_WIDTH with the
bit DP_HOST_TRIPLE_EN set (from previous invocation), the driver would
never ever clear the bit, resulting in display corruption.
We don't want to wait for idle because it would degrade performance, so
this patch modifies the driver so that it never reads accelerator
registers.
HOST_CNTL doesn't have to be read, we can just write it with
HOST_BYTE_ALIGN because no other part of the driver cares if
HOST_BYTE_ALIGN is set.
DP_PIX_WIDTH is written in the functions atyfb_copyarea and atyfb_fillrect
with the default value and in atyfb_imageblit with the value set according
to the source image data.
The code for manual bit triple is not endian-clean. It builds the variable
"hostdword" using byte accesses, therefore we must read the variable with
"le32_to_cpu".
The patch also enables (hardware or software) bit triple only if the image
is monochrome (image->depth). If we want to blit full-color image, we
shouldn't use the triple code.
Moving the bcm2835 thermal driver to the broadcom directory prevented it
from getting enabled for arm64 builds, since the broadcom directory is only
available when 32-bit specific ARCH_BCM is set.
Fix this by enabling the Broadcom menu for ARCH_BCM or ARCH_BCM2835.
Fixes: 6892cf07e733 ("thermal: bcm2835: move to the broadcom subdirectory") Reviewed-by: Eric Anholt <eric@anholt.net> Signed-off-by: Allen Wild <allenwild93@gmail.com> Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Eduardo Valentin <edubezval@gmail.com> Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
splice_dentry() is used by three places. For two places, req->r_dentry
is passed to splice_dentry(). In the case of error, req->r_dentry does
not get updated. So splice_dentry() should not drop reference.
Fixes the signedness bug returning '(-22)' on the return type by removing the
sanity checker in rockchip_ddrclk_get_parent(). The function should return
and unsigned value only and it's safe to remove the sanity checker as the
core functions that call get_parent like clk_core_get_parent_by_index already
ensures the validity of the clk index returned (index >= core->num_parents).
Fixes: a4f182bf81f18 ("clk: rockchip: add new clock-type for the ddrclk") Cc: stable@vger.kernel.org Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> Reviewed-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit a982e45dc150 ("clk: at91: PLL recalc_rate() now using cached MUL
and DIV values") removed a check that prevents a division by zero. This
now causes a stacktrace when booting the kernel on a at91 platform if
the PLL DIV register contains zero. This commit reintroduces this check.
Fixes: a982e45dc150 ("clk: at91: PLL recalc_rate() now using cached...") Cc: <stable@vger.kernel.org> Signed-off-by: Ronald Wahl <rwahl@gmx.de> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When driver is built as module and DT node contains clocks compatible
(e.g. "samsung,s2mps11-clk"), the module will not be autoloaded because
module aliases won't match.
The modalias from uevent: of:NclocksT<NULL>Csamsung,s2mps11-clk
The modalias from driver: platform:s2mps11-clk
The devices are instantiated by parent's MFD. However both Device Tree
bindings and parent define the compatible for clocks devices. In case
of module matching this DT compatible will be used.
The issue will not happen if this is a built-in (no need for module
matching) or when clocks DT node does not contain compatible (not
correct from bindings perspective but working for driver).
Note when backporting to stable kernels: adjust the list of device ID
entries.
Cc: <stable@vger.kernel.org> Fixes: 53c31b3437a6 ("mfd: sec-core: Add of_compatible strings for clock MFD cells") Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Acked-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
32bit UML used to define PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP
own its own because many years ago not all libcs had these request codes
in their UAPI.
These days PTRACE_SYSEMU/_SINGLESTEP is well known and part of glibc
and our own define becomes problematic.
With change c48831d0eebf ("linux/x86: sync sys/ptrace.h with Linux 4.14
[BZ #22433]") glibc turned PTRACE_SYSEMU/_SINGLESTEP into a enum and
UML failed to build.
Let's drop our define and rely on the fact that every libc has
PTRACE_SYSEMU/_SINGLESTEP.
The bootloader may pass physical address of the boot parameters structure
to the MMUv3 kernel in the register a2. Code in the _SetupMMU block in
the arch/xtensa/kernel/head.S is supposed to map that physical address to
the virtual address in the configured virtual memory layout.
This code haven't been updated when additional 256+256 and 512+512
memory layouts were introduced and it may produce wrong addresses when
used with these layouts.
Cc: stable@vger.kernel.org Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Xtensa ABI requires stack alignment to be at least 16. In noMMU
configuration ARCH_SLAB_MINALIGN is used to align stack. Make it at
least 16.
This fixes the following runtime error in noMMU configuration, caused by
interaction between insufficiently aligned stack and alloca function,
that results in corruption of on-stack variable in the libc function
glob:
Caught unhandled exception in 'sh' (pid = 47, pc = 0x02d05d65)
- should not happen
EXCCAUSE is 15
Cc: stable@vger.kernel.org Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This section collects all source .note.* sections together in the
vmlinux image. Without it .note.Linux section may be placed at address
0, while the rest of the kernel is at its normal address, resulting in a
huge vmlinux.bin image that may not be linked into the xtensa Image.elf.
Cc: stable@vger.kernel.org Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After commit e509bd7da149dc349160 ("genirq: Allow migration of chained
interrupts by installing default action") Loongson-3 fails at here:
setup_irq(LOONGSON_HT1_IRQ, &cascade_irqaction);
This is because both chained_action and cascade_irqaction don't have
IRQF_SHARED flag. This will cause Loongson-3 resume fails because HPET
timer interrupt can't be delivered during S3. So we set the irqchip of
the chained irq to loongson_irq_chip which doesn't disable the chained
irq in CP0.Status.
Masking/unmasking the CPU UART irq in CP0_Status (and redirecting it to
other CPUs) may cause interrupts be lost, especially in multi-package
machines (Package-0's UART irq cannot be delivered to others). So make
mask_loongson_irq() and unmask_loongson_irq() be no-ops.
The original problem (UART IRQ may deliver to any core) is also because
of masking/unmasking the CPU UART irq in CP0_Status. So it is safe to
remove all of the stuff.
linking a non-copied-up file into a non-copied-up parent results in a
nested call to mutex_lock_interruptible(&oi->lock). Fix this by copying up
target parent before ovl_nlink_start(), same as done in ovl_rename().
Otherwise fuse_dev_do_write() could come in and finish off the request, and
the set_bit(FR_SENT, ...) could trigger the WARN_ON(test_bit(FR_SENT, ...))
in request_end().
Using waitqueue_active() is racy. Make sure we issue a wake_up()
unconditionally after storing into fc->blocked. After that it's okay to
optimize with waitqueue_active() since the first wake up provides the
necessary barrier for all waiters, not the just the woken one.
This patch fixes issue where driver clears NPort ID map instead of marking
handle in use. Once driver clears NPort ID from the database, it can reuse
the same NPort ID resulting in a PLOGI failure.
[mkp: fixed Himanshu's SoB]
Fixes: a084fd68e1d2 ("scsi: qla2xxx: Fix re-login for Nport Handle in use") Cc: <stable@vger.kernel.org> Signed-of-by: Quinn Tran <quinn.tran@cavium.com> Reviewed-by: Ewan D. Milne <emilne@redhat.com> Signed-off-by: Himanshu Madhani <hmadhani@cavium.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
projects / linux-stable / log