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Linux kernel
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Pull ceph fixes from Ilya Dryomov:
"A change to call iput() asynchronously to avoid a possible deadlock
when iput_final() needs to wait for in-flight I/O (e.g. readahead) and
a fixup for a cleanup that went into -rc1"
* tag 'ceph-for-5.2-rc4' of git://github.com/ceph/ceph-client:
ceph: fix error handling in ceph_get_caps()
ceph: avoid iput_final() while holding mutex or in dispatch thread
ceph: single workqueue for inode related works
Pull xen fix from Juergen Gross:
"Just one fix for the Xen block frontend driver avoiding allocations
with order > 0"
* tag 'for-linus-5.2b-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen-blkfront: switch kcalloc to kvcalloc for large array allocation
The function return 0 even when interrupted or try_get_cap_refs()
return error.
Fixes: 1199d7da2d ("ceph: simplify arguments and return semantics of try_get_cap_refs")
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Pull s390 fixes from Heiko Carstens:
- fix stack unwinder: the stack unwinder rework has on off-by-one bug
which prevents following stack backchains over more than one context
(e.g. irq -> process).
- fix address space detection in exception handler: if user space
switches to access register mode, which is not supported anymore, the
exception handler may resolve to the wrong address space.
* tag 's390-5.2-4' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/unwind: correct stack switching during unwind
s390/mm: fix address space detection in exception handling
There's no reason to request physically contiguous memory for those
allocations.
[boris: added CC to stable]
Cc: stable@vger.kernel.org
Reported-by: Ian Jackson <ian.jackson@citrix.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
iput_final() may wait for reahahead pages. The wait can cause deadlock.
For example:
Workqueue: ceph-msgr ceph_con_workfn [libceph]
Call Trace:
schedule+0x36/0x80
io_schedule+0x16/0x40
__lock_page+0x101/0x140
truncate_inode_pages_range+0x556/0x9f0
truncate_inode_pages_final+0x4d/0x60
evict+0x182/0x1a0
iput+0x1d2/0x220
iterate_session_caps+0x82/0x230 [ceph]
dispatch+0x678/0xa80 [ceph]
ceph_con_workfn+0x95b/0x1560 [libceph]
process_one_work+0x14d/0x410
worker_thread+0x4b/0x460
kthread+0x105/0x140
ret_from_fork+0x22/0x40
Workqueue: ceph-msgr ceph_con_workfn [libceph]
Call Trace:
__schedule+0x3d6/0x8b0
schedule+0x36/0x80
schedule_preempt_disabled+0xe/0x10
mutex_lock+0x2f/0x40
ceph_check_caps+0x505/0xa80 [ceph]
ceph_put_wrbuffer_cap_refs+0x1e5/0x2c0 [ceph]
writepages_finish+0x2d3/0x410 [ceph]
__complete_request+0x26/0x60 [libceph]
handle_reply+0x6c8/0xa10 [libceph]
dispatch+0x29a/0xbb0 [libceph]
ceph_con_workfn+0x95b/0x1560 [libceph]
process_one_work+0x14d/0x410
worker_thread+0x4b/0x460
kthread+0x105/0x140
ret_from_fork+0x22/0x40
In above example, truncate_inode_pages_range() waits for readahead pages
while holding s_mutex. ceph_check_caps() waits for s_mutex and blocks
OSD dispatch thread. Later OSD replies (for readahead) can't be handled.
ceph_check_caps() also may lock snap_rwsem for read. So similar deadlock
can happen if iput_final() is called while holding snap_rwsem.
In general, it's not good to call iput_final() inside MDS/OSD dispatch
threads or while holding any mutex.
The fix is introducing ceph_async_iput(), which calls iput_final() in
workqueue.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Pull MIPS fixes from Paul Burton:
- Declare ginvt() __always_inline due to its use of an argument as an
inline asm immediate.
- A VDSO build fix following Kbuild changes made this cycle.
- A fix for boot failures on txx9 systems following memory
initialization changes made this cycle.
- Bounds check virt_addr_valid() to prevent it spuriously indicating
that bogus addresses are valid, in turn fixing hardened usercopy
failures that have been present since v4.12.
- Build uImage.gz for pistachio systems by default, since this is the
image we need in order to actually boot on a board.
- Remove an unused variable in our uprobes code.
* tag 'mips_fixes_5.2_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
MIPS: uprobes: remove set but not used variable 'epc'
MIPS: pistachio: Build uImage.gz by default
MIPS: Make virt_addr_valid() return bool
MIPS: Bounds check virt_addr_valid
MIPS: TXx9: Fix boot crash in free_initmem()
MIPS: remove a space after -I to cope with header search paths for VDSO
MIPS: mark ginvt() as __always_inline
Adjust conditions in on_stack function. That fixes backchain unwinder
which was unable to read pt_regs at the very bottom of the stack and
hence couldn't follow stacks (e.g. from async stack to a task stack).
Fixes: 78c98f907413 ("s390/unwind: introduce stack unwind API")
Reported-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
During a suspend/resume, the xenwatch thread waits for all outstanding
xenstore requests and transactions to complete. This does not work
correctly for transactions started by userspace because it waits for
them to complete after freezing userspace threads which means the
transactions have no way of completing, resulting in a deadlock. This is
trivial to reproduce by running this script and then suspending the VM:
import pyxs, time
c = pyxs.client.Client(xen_bus_path="/dev/xen/xenbus")
c.connect()
c.transaction()
time.sleep(3600)
Even if this deadlock were resolved, misbehaving userspace should not
prevent a VM from being migrated. So, instead of waiting for these
transactions to complete before suspending, store the current generation
id for each transaction when it is started. The global generation id is
incremented during resume. If the caller commits the transaction and the
generation id does not match the current generation id, return EAGAIN so
that they try again. If the transaction was instead discarded, return OK
since no changes were made anyway.
This only affects users of the xenbus file interface. In-kernel users of
xenbus are assumed to be well-behaved and complete all transactions
before freezing.
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
We have three workqueue for inode works. Later patch will introduce
one more work for inode. It's not good to introcuce more workqueue
and add more 'struct work_struct' to 'struct ceph_inode_info'.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Pull yet more SPDX updates from Greg KH:
"Another round of SPDX header file fixes for 5.2-rc4
These are all more "GPL-2.0-or-later" or "GPL-2.0-only" tags being
added, based on the text in the files. We are slowly chipping away at
the 700+ different ways people tried to write the license text. All of
these were reviewed on the spdx mailing list by a number of different
people.
We now have over 60% of the kernel files covered with SPDX tags:
$ ./scripts/spdxcheck.py -v 2>&1 | grep Files
Files checked: 64533
Files with SPDX: 40392
Files with errors: 0
I think the majority of the "easy" fixups are now done, it's now the
start of the longer-tail of crazy variants to wade through"
* tag 'spdx-5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (159 commits)
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 450
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 449
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 448
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 446
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 445
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 444
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 443
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 442
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 440
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 438
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 437
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 436
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 435
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 434
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 433
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 432
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 431
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 430
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 429
...
Fixes gcc '-Wunused-but-set-variable' warning:
arch/mips/kernel/uprobes.c: In function 'arch_uprobe_pre_xol':
arch/mips/kernel/uprobes.c:115:17: warning: variable 'epc' set but not used [-Wunused-but-set-variable]
It's never used since introduction in
commit 40e084a506eb ("MIPS: Add uprobes support.")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: <ralf@linux-mips.org>
Cc: <jhogan@kernel.org>
Cc: <linux-kernel@vger.kernel.org>
Cc: <linux-mips@vger.kernel.org>
Commit 0aaba41b58bc ("s390: remove all code using the access register
mode") removed access register mode from the kernel, and also from the
address space detection logic. However, user space could still switch
to access register mode (trans_exc_code == 1), and exceptions in that
mode would not be correctly assigned.
Fix this by adding a check for trans_exc_code == 1 to get_fault_type(),
and remove the wrong comment line before that function.
Fixes: 0aaba41b58bc ("s390: remove all code using the access register mode")
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: <stable@vger.kernel.org> # v4.15+
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
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