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The current comment for the barrier that guarantees that waiter increment
is always before taking the hb spinlock (barrier (A)) needs to be fixed as
it is misplaced.
This is obviously referring to hb_waiters_inc, which is a full barrier.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190206185602.949-1-dave@stgolabs.net
Pull x86 platform driver fixlet from Darren Hart:
"Correct Documentation/ABI 4.21 KernelVersion to 5.0"
* tag 'platform-drivers-x86-v5.0-2' of git://git.infradead.org/linux-platform-drivers-x86:
Documentation/ABI: Correct mlxreg-io KernelVersion for 5.0
Pull KVM fixes from Paolo Bonzini:
"Three security fixes"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: nVMX: unconditionally cancel preemption timer in free_nested (CVE-2019-7221)
KVM: x86: work around leak of uninitialized stack contents (CVE-2019-7222)
kvm: fix kvm_ioctl_create_device() reference counting (CVE-2019-6974)
The mlxreg-io for the merge window assumed 4.21 as the next kernel
version. Replace 4.21 with 5.0.
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Pull nfsd fixes from Bruce Fields:
"Two small nfsd bugfixes for 5.0, for an RDMA bug and a file clone bug"
* tag 'nfsd-5.0-1' of git://linux-nfs.org/~bfields/linux:
svcrdma: Remove max_sge check at connect time
nfsd: Fix error return values for nfsd4_clone_file_range()
Bugzilla: 1671904
There are multiple code paths where an hrtimer may have been started to
emulate an L1 VMX preemption timer that can result in a call to free_nested
without an intervening L2 exit where the hrtimer is normally
cancelled. Unconditionally cancel in free_nested to cover all cases.
Embargoed until Feb 7th 2019.
Signed-off-by: Peter Shier <pshier@google.com>
Reported-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Reported-by: Felix Wilhelm <fwilhelm@google.com>
Cc: stable@kernel.org
Message-Id: <20181011184646.154065-1-pshier@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull device mapper fixes from Mike Snitzer:
"Both of these fixes address issues in changes merged for 5.0-rc4:
- Fix DM core's missing memory barrier before waitqueue_active()
calls.
- Fix DM core's clone_bio() to work when cloning a subset of a bio
with an integrity payload; bio_integrity_trim() wasn't getting
called due to bio_trim()'s early return"
* tag 'for-5.0/dm-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm: don't use bio_trim() afterall
dm: add memory barrier before waitqueue_active
Two and a half years ago, the client was changed to use gathered
Send for larger inline messages, in commit 655fec6987b ("xprtrdma:
Use gathered Send for large inline messages"). Several fixes were
required because there are a few in-kernel device drivers whose
max_sge is 3, and these were broken by the change.
Apparently my memory is going, because some time later, I submitted
commit 25fd86eca11c ("svcrdma: Don't overrun the SGE array in
svc_rdma_send_ctxt"), and after that, commit f3c1fd0ee294 ("svcrdma:
Reduce max_send_sges"). These too incorrectly assumed in-kernel
device drivers would have more than a few Send SGEs available.
The fix for the server side is not the same. This is because the
fundamental problem on the server is that, whether or not the client
has provisioned a chunk for the RPC reply, the server must squeeze
even the most complex RPC replies into a single RDMA Send. Failing
in the send path because of Send SGE exhaustion should never be an
option.
Therefore, instead of failing when the send path runs out of SGEs,
switch to using a bounce buffer mechanism to handle RPC replies that
are too complex for the device to send directly. That allows us to
remove the max_sge check to enable drivers with small max_sge to
work again.
Reported-by: Don Dutile <ddutile@redhat.com>
Fixes: 25fd86eca11c ("svcrdma: Don't overrun the SGE array in ...")
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Bugzilla: 1671930
Emulation of certain instructions (VMXON, VMCLEAR, VMPTRLD, VMWRITE with
memory operand, INVEPT, INVVPID) can incorrectly inject a page fault
when passed an operand that points to an MMIO address. The page fault
will use uninitialized kernel stack memory as the CR2 and error code.
The right behavior would be to abort the VM with a KVM_EXIT_INTERNAL_ERROR
exit to userspace; however, it is not an easy fix, so for now just
ensure that the error code and CR2 are zero.
Embargoed until Feb 7th 2019.
Reported-by: Felix Wilhelm <fwilhelm@google.com>
Cc: stable@kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull pstore fixes from Kees Cook:
- Fix console ramoops to show the previous boot logs (Sai Prakash
Ranjan)
- Avoid allocation and leak of platform data
* tag 'pstore-v5.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
pstore/ram: Avoid allocation and leak of platform data
pstore/ram: Fix console ramoops to show the previous boot logs
Pull HID fix from Jiri Kosina:
"A fix for a bug in hid-debug that can lock up the kernel in infinite
loop (CVE-2019-3819), from Vladis Dronov"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid:
HID: debug: fix the ring buffer implementation
bio_trim() has an early return, which makes it _not_ idempotent, if the
offset is 0 and the bio's bi_size already matches the requested size.
Prior to DM, all users of bio_trim() were fine with this. But DM has
exposed the fact that bio_trim()'s early return is incompatible with a
cloned bio whose integrity payload must be trimmed via
bio_integrity_trim().
Fix this by reverting DM back to doing the equivalent of bio_trim() but
in an idempotent manner (so bio_integrity_trim is always performed).
Follow-on work is needed to assess what benefit bio_trim()'s early
return is providing to its existing callers.
Reported-by: Milan Broz <gmazyland@gmail.com>
Fixes: 57c36519e4b94 ("dm: fix clone_bio() to trigger blk_recount_segments()")
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
If the parameter 'count' is non-zero, nfsd4_clone_file_range() will
currently clobber all errors returned by vfs_clone_file_range() and
replace them with EINVAL.
Fixes: 42ec3d4c0218 ("vfs: make remap_file_range functions take and...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org # v4.20+
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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