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457,582 commits

Author SHA1 Message Date
Amos Kong
d024fb8a37 virtio-rng: fix stuck of hot-unplugging busy device
commit 3856e54837 upstream.

When we try to hot-remove a busy virtio-rng device from QEMU monitor,
the device can't be hot-removed. Because virtio-rng driver hangs at
wait_for_completion_killable().

This patch exits the waiting by completing have_data completion before
unregistering, resets data_avail to avoid the hwrng core use wrong
buffer bytes.

Signed-off-by: Amos Kong <akong@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 15:54:09 +00:00
David Dueck
d5b57d6538 can: at91_can: add missing prepare and unprepare of the clock
commit e77980e50b upstream.

In order to make the driver work with the common clock framework, this patch
converts the clk_enable()/clk_disable() to
clk_prepare_enable()/clk_disable_unprepare(). While there, add the missing
error handling.

Signed-off-by: David Dueck <davidcdueck@googlemail.com>
Signed-off-by: Anthony Harivel <anthony.harivel@emtrion.de>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 14:14:45 +00:00
Marc Kleine-Budde
fbca5accde can: flexcan: put TX mailbox into TX_INACTIVE mode after tx-complete
commit de5944883e upstream.

After sending a RTR frame the TX mailbox becomes a RX_EMPTY mailbox. To avoid
side effects when the RX-FIFO is full, this patch puts the TX mailbox into
TX_INACTIVE mode in the transmission complete interrupt handler. This, of
course, leaves a race window between the actual completion of the transmission
and the handling of tx-complete interrupt. However this is the best we can do
without busy polling the tx complete interrupt.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 14:14:44 +00:00
David Jander
1a9500cc03 can: flexcan: implement workaround for errata ERR005829
commit 25e924450f upstream.

This patch implements the workaround mentioned in ERR005829:

    ERR005829: FlexCAN: FlexCAN does not transmit a message that is enabled to
    be transmitted in a specific moment during the arbitration process.

Workaround: The workaround consists of two extra steps after setting up a
message for transmission:

Step 8: Reserve the first valid mailbox as an inactive mailbox (CODE=0b1000).
If RX FIFO is disabled, this mailbox must be message buffer 0. Otherwise, the
first valid mailbox can be found using the "RX FIFO filters" table in the
FlexCAN chapter of the chip reference manual.

Step 9: Write twice INACTIVE code (0b1000) into the first valid mailbox.

Signed-off-by: David Jander <david@protonic.nl>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 14:14:44 +00:00
David Jander
d4e9b1e783 can: flexcan: correctly initialize mailboxes
commit fc05b884a3 upstream.

Apparently mailboxes may contain random data at startup, causing some of them
being prepared for message reception. This causes overruns being missed or even
confusing the IRQ check for trasmitted messages, increasing the transmit
counter instead of the error counter.

This patch initializes all mailboxes after the FIFO as RX_INACTIVE.

Signed-off-by: David Jander <david@protonic.nl>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 14:14:44 +00:00
Marc Kleine-Budde
ba69191491 can: flexcan: mark TX mailbox as TX_INACTIVE
commit c32fe4ad3e upstream.

This patch fixes the initialization of the TX mailbox. It is now correctly
initialized as TX_INACTIVE not RX_EMPTY.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 14:14:43 +00:00
Al Viro
3ff4c0b892 be careful with nd->inode in path_init() and follow_dotdot_rcu()
commit 4023bfc9f3 upstream.

in the former we simply check if dentry is still valid after picking
its ->d_inode; in the latter we fetch ->d_inode in the same places
where we fetch dentry and its ->d_seq, under the same checks.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 14:14:43 +00:00
Josh Triplett
52dafa6920 init/Kconfig: Hide printk log config if CONFIG_PRINTK=n
commit 361e9dfbaa upstream.

The buffers sized by CONFIG_LOG_BUF_SHIFT and
CONFIG_LOG_CPU_MAX_BUF_SHIFT do not exist if CONFIG_PRINTK=n, so don't
ask about their size at all.

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
[ kamal: backport to 3.13-stable: only LOG_BUF_SHIFT ]
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 13:55:02 +00:00
Nadav Amit
7055e77df5 KVM: x86: Fix far-jump to non-canonical check
commit 7e46dddd6f upstream.

Commit d1442d85cc ("KVM: x86: Handle errors when RIP is set during far
jumps") introduced a bug that caused the fix to be incomplete.  Due to
incorrect evaluation, far jump to segment with L bit cleared (i.e., 32-bit
segment) and RIP with any of the high bits set (i.e, RIP[63:32] != 0) set may
not trigger #GP.  As we know, this imposes a security problem.

In addition, the condition for two warnings was incorrect.

Fixes: d1442d85cc
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
[Add #ifdef CONFIG_X86_64 to avoid complaints of undefined behavior. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:13 +00:00
Quentin Casasnovas
74be68b2ab kvm: fix excessive pages un-pinning in kvm_iommu_map error path.
commit 3d32e4dbe7 upstream.

The third parameter of kvm_unpin_pages() when called from
kvm_iommu_map_pages() is wrong, it should be the number of pages to un-pin
and not the page size.

This error was facilitated with an inconsistent API: kvm_pin_pages() takes
a size, but kvn_unpin_pages() takes a number of pages, so fix the problem
by matching the two.

This was introduced by commit 350b8bd ("kvm: iommu: fix the third parameter
of kvm_iommu_put_pages (CVE-2014-3601)"), which fixes the lack of
un-pinning for pages intended to be un-pinned (i.e. memory leak) but
unfortunately potentially aggravated the number of pages we un-pin that
should have stayed pinned. As far as I understand though, the same
practical mitigations apply.

This issue was found during review of Red Hat 6.6 patches to prepare
Ksplice rebootless updates.

Thanks to Vegard for his time on a late Friday evening to help me in
understanding this code.

Fixes: 350b8bd ("kvm: iommu: fix the third parameter of... (CVE-2014-3601)")
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Jamie Iles <jamie.iles@oracle.com>
Reviewed-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:13 +00:00
Michael S. Tsirkin
395f428dc3 kvm: x86: don't kill guest on unknown exit reason
commit 2bc19dc375 upstream.

KVM_EXIT_UNKNOWN is a kvm bug, we don't really know whether it was
triggered by a priveledged application.  Let's not kill the guest: WARN
and inject #UD instead.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:13 +00:00
Petr Matousek
67fe3bc3d2 kvm: vmx: handle invvpid vm exit gracefully
commit a642fc3050 upstream.

On systems with invvpid instruction support (corresponding bit in
IA32_VMX_EPT_VPID_CAP MSR is set) guest invocation of invvpid
causes vm exit, which is currently not handled and results in
propagation of unknown exit to userspace.

Fix this by installing an invvpid vm exit handler.

This is CVE-2014-3646.

Signed-off-by: Petr Matousek <pmatouse@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:13 +00:00
Nadav Amit
0e8f14df9b KVM: x86: Handle errors when RIP is set during far jumps
commit d1442d85cc upstream.

Far jmp/call/ret may fault while loading a new RIP.  Currently KVM does not
handle this case, and may result in failed vm-entry once the assignment is
done.  The tricky part of doing so is that loading the new CS affects the
VMCS/VMCB state, so if we fail during loading the new RIP, we are left in
unconsistent state.  Therefore, this patch saves on 64-bit the old CS
descriptor and restores it if loading RIP failed.

This fixes CVE-2014-3647.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:12 +00:00
Nadav Amit
8a909b2c6e KVM: x86: Emulator fixes for eip canonical checks on near branches
commit 234f3ce485 upstream.

Before changing rip (during jmp, call, ret, etc.) the target should be asserted
to be canonical one, as real CPUs do.  During sysret, both target rsp and rip
should be canonical. If any of these values is noncanonical, a #GP exception
should occur.  The exception to this rule are syscall and sysenter instructions
in which the assigned rip is checked during the assignment to the relevant
MSRs.

This patch fixes the emulator to behave as real CPUs do for near branches.
Far branches are handled by the next patch.

This fixes CVE-2014-3647.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:12 +00:00
Nadav Amit
ee37854de0 KVM: x86: Fix wrong masking on relative jump/call
commit 05c83ec9b7 upstream.

Relative jumps and calls do the masking according to the operand size, and not
according to the address size as the KVM emulator does today.

This patch fixes KVM behavior.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:12 +00:00
Andy Honig
262400a71a KVM: x86: Improve thread safety in pit
commit 2febc83913 upstream.

There's a race condition in the PIT emulation code in KVM.  In
__kvm_migrate_pit_timer the pit_timer object is accessed without
synchronization.  If the race condition occurs at the wrong time this
can crash the host kernel.

This fixes CVE-2014-3611.

Signed-off-by: Andrew Honig <ahonig@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:12 +00:00
Andy Honig
78c4e45457 KVM: x86: Prevent host from panicking on shared MSR writes.
commit 8b3c3104c3 upstream.

The previous patch blocked invalid writes directly when the MSR
is written.  As a precaution, prevent future similar mistakes by
gracefulling handle GPs caused by writes to shared MSRs.

Signed-off-by: Andrew Honig <ahonig@google.com>
[Remove parts obsoleted by Nadav's patch. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:11 +00:00
Nadav Amit
604acafa52 KVM: x86: Check non-canonical addresses upon WRMSR
commit 854e8bb1aa upstream.

Upon WRMSR, the CPU should inject #GP if a non-canonical value (address) is
written to certain MSRs. The behavior is "almost" identical for AMD and Intel
(ignoring MSRs that are not implemented in either architecture since they would
anyhow #GP). However, IA32_SYSENTER_ESP and IA32_SYSENTER_EIP cause #GP if
non-canonical address is written on Intel but not on AMD (which ignores the top
32-bits).

Accordingly, this patch injects a #GP on the MSRs which behave identically on
Intel and AMD.  To eliminate the differences between the architecutres, the
value which is written to IA32_SYSENTER_ESP and IA32_SYSENTER_EIP is turned to
canonical value before writing instead of injecting a #GP.

Some references from Intel and AMD manuals:

According to Intel SDM description of WRMSR instruction #GP is expected on
WRMSR "If the source register contains a non-canonical address and ECX
specifies one of the following MSRs: IA32_DS_AREA, IA32_FS_BASE, IA32_GS_BASE,
IA32_KERNEL_GS_BASE, IA32_LSTAR, IA32_SYSENTER_EIP, IA32_SYSENTER_ESP."

According to AMD manual instruction manual:
LSTAR/CSTAR (SYSCALL): "The WRMSR instruction loads the target RIP into the
LSTAR and CSTAR registers.  If an RIP written by WRMSR is not in canonical
form, a general-protection exception (#GP) occurs."
IA32_GS_BASE and IA32_FS_BASE (WRFSBASE/WRGSBASE): "The address written to the
base field must be in canonical form or a #GP fault will occur."
IA32_KERNEL_GS_BASE (SWAPGS): "The address stored in the KernelGSbase MSR must
be in canonical form."

This patch fixes CVE-2014-3610.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:11 +00:00
Markos Chandras
7763c7e651 MIPS: ftrace: Fix a microMIPS build problem
commit aedd153f5b upstream.

Code before the .fixup section needs to have the .insn directive.
This has no side effects on MIPS32/64 but it affects the way microMIPS
loads the address for the return label.

Fixes the following build problem:
mips-linux-gnu-ld: arch/mips/built-in.o: .fixup+0x4a0: Unsupported jump between
ISA modes; consider recompiling with interlinking enabled.
mips-linux-gnu-ld: final link failed: Bad value
Makefile:819: recipe for target 'vmlinux' failed

The fix is similar to 1658f914ff ("MIPS: microMIPS:
Disable LL/SC and fix linker bug.")

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8117/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:11 +00:00
Dirk Brandewie
09789f41b1 intel_pstate: Correct BYT VID values.
commit d022a65ed2 upstream.

Using a VID value that is not high enough for the requested P state can
cause machine checks. Add a ceiling function to ensure calulated VIDs
with fractional values are set to the next highest integer VID value.

The algorythm for calculating the non-trubo VID from the BIOS writers
guide is:
 vid_ratio = (vid_max - vid_min) / (max_pstate - min_pstate)
 vid = ceiling(vid_min + (req_pstate - min_pstate) * vid_ratio)

Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:11 +00:00
Dirk Brandewie
7722e90cd4 intel_pstate: Fix BYT frequency reporting
commit b27580b05e upstream.

BYT has a different conversion from P state to frequency than the core
processors.  This causes the min/max and current frequency to be
misreported on some BYT SKUs. Tested on BYT N2820, Ivybridge and
Haswell processors.

Link: https://bugzilla.yoctoproject.org/show_bug.cgi?id=6663
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:11 +00:00
Dirk Brandewie
0f45c61ff4 intel_pstate: Don't lose sysfs settings during cpu offline
commit c034871712 upstream.

The user may have custom settings don't destroy them during suspend.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=80651
Reported-by: Tobias Jakobi <liquid.acid@gmx.net>
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:10 +00:00
Gabriele Mazzotta
e3a500847b cpufreq: intel_pstate: Reflect current no_turbo state correctly
commit 4521e1a0ce upstream.

Some BIOSes modify the state of MSR_IA32_MISC_ENABLE_TURBO_DISABLE
based on the current power source for the system battery AC vs
battery. Reflect the correct current state and ability to modify the
no_turbo sysfs file based on current state of
MSR_IA32_MISC_ENABLE_TURBO_DISABLE.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=83151
Signed-off-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:10 +00:00
Dirk Brandewie
98198820e5 cpufreq: expose scaling_cur_freq sysfs file for set_policy() drivers
commit c034b02e21 upstream.

Currently the core does not expose scaling_cur_freq for set_policy()
drivers this breaks some userspace monitoring tools.
Change the core to expose this file for all drivers and if the
set_policy() driver supports the get() callback use it to retrieve the
current frequency.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=73741
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:10 +00:00
Pali Rohár
829ff274b9 cpufreq: intel_pstate: Fix setting max_perf_pct in performance policy
commit 36b4bed5cd upstream.

Code which changes policy to powersave changes also max_policy_pct based on
max_freq. Code which change max_perf_pct has upper limit base on value
max_policy_pct. When policy is changing from powersave back to performance
then max_policy_pct is not changed. Which means that changing max_perf_pct is
not possible to high values if max_freq was too low in powersave policy.

Test case:

$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
800000
$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
3300000
$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
performance
$ cat /sys/devices/system/cpu/intel_pstate/max_perf_pct
100

$ echo powersave > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
$ echo 800000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
$ echo 20 > /sys/devices/system/cpu/intel_pstate/max_perf_pct

$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
powersave
$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
800000
$ cat /sys/devices/system/cpu/intel_pstate/max_perf_pct
20

$ echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
$ echo 3300000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
$ echo 100 > /sys/devices/system/cpu/intel_pstate/max_perf_pct

$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
performance
$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
3300000
$ cat /sys/devices/system/cpu/intel_pstate/max_perf_pct
24

And now intel_pstate driver allows to set maximal value for max_perf_pct based
on max_policy_pct which is 24 for previous powersave max_freq 800000.

This patch will set default value for max_policy_pct when setting policy to
performance so it will allow to set also max value for max_perf_pct.

Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Acked-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:10 +00:00
Olaf Hering
66270312ca drm/cirrus: bind also to qemu-xen-traditional
commit c0c3e735fa upstream.

qemu as used by xend/xm toolstack uses a different subvendor id.
Bind the drm driver also to this emulated card.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:10 +00:00
David Daney
e00341304d MIPS: tlbex: Properly fix HUGE TLB Refill exception handler
commit 9e0f162a36 upstream.

In commit 8393c524a2 (MIPS: tlbex: Fix a missing statement for
HUGETLB), the TLB Refill handler was fixed so that non-OCTEON targets
would work properly with huge pages.  The change was incorrect in that
it broke the OCTEON case.

The problem is shown here:

    xxx0:	df7a0000 	ld	k0,0(k1)
    .
    .
    .
    xxxc0:	df610000 	ld	at,0(k1)
    xxxc4:	335a0ff0 	andi	k0,k0,0xff0
    xxxc8:	e825ffcd 	bbit1	at,0x5,0x0
    xxxcc:	003ad82d 	daddu	k1,at,k0
    .
    .
    .

In the non-octeon case there is a destructive test for the huge PTE
bit, and then at 0, $k0 is reloaded (that is what the 8393c524a2
patch added).

In the octeon case, we modify k1 in the branch delay slot, but we
never need k0 again, so the new load is not needed, but since k1 is
modified, if we do the load, we load from a garbage location and then
get a nested TLB Refill, which is seen in userspace as either SIGBUS
or SIGSEGV (depending on the garbage).

The real fix is to only do this reloading if it is needed, and never
where it is harmful.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8151/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:09 +00:00
Aaro Koskinen
f563a83bc7 MIPS: loongson2_cpufreq: Fix CPU clock rate setting mismerge
commit aa08ed5544 upstream.

During 3.16 merge window, parts of the commit 8e8acb3296
(MIPS/loongson2_cpufreq: Fix CPU clock rate setting) seem to have
been deleted probably due to a mismerge, and as a result cpufreq
is broken again on Loongson2 boards in 3.16 and newer kernels.
Fix by repeating the fix.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7835/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:09 +00:00
Marc-André Lureau
faabb12bd2 qxl: don't create too large primary surface
commit c572aaf46f upstream.

Limit primary to qemu vgamem size, to avoid reaching
qemu guest bug "requested primary larger than framebuffer"
on resizing screen too large to fit.

Remove unneeded and misleading variables.

Related to:
https://bugzilla.redhat.com/show_bug.cgi?id=1127552

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:09 +00:00
Michal Hocko
7e35ef0434 OOM, PM: OOM killed task shouldn't escape PM suspend
commit 5695be142e upstream.

PM freezer relies on having all tasks frozen by the time devices are
getting frozen so that no task will touch them while they are getting
frozen. But OOM killer is allowed to kill an already frozen task in
order to handle OOM situtation. In order to protect from late wake ups
OOM killer is disabled after all tasks are frozen. This, however, still
keeps a window open when a killed task didn't manage to die by the time
freeze_processes finishes.

Reduce the race window by checking all tasks after OOM killer has been
disabled. This is still not race free completely unfortunately because
oom_killer_disable cannot stop an already ongoing OOM killer so a task
might still wake up from the fridge and get killed without
freeze_processes noticing. Full synchronization of OOM and freezer is,
however, too heavy weight for this highly unlikely case.

Introduce and check oom_kills counter which gets incremented early when
the allocator enters __alloc_pages_may_oom path and only check all the
tasks if the counter changes during the freezing attempt. The counter
is updated so early to reduce the race window since allocator checked
oom_killer_disabled which is set by PM-freezing code. A false positive
will push the PM-freezer into a slow path but that is not a big deal.

Changes since v1
- push the re-check loop out of freeze_processes into
  check_frozen_processes and invert the condition to make the code more
  readable as per Rafael

Fixes: f660daac47 (oom: thaw threads if oom killed thread is frozen before deferring)
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:09 +00:00
Cong Wang
c76a927631 freezer: Do not freeze tasks killed by OOM killer
commit 51fae6da64 upstream.

Since f660daac47 (oom: thaw threads if oom killed thread is frozen
before deferring) OOM killer relies on being able to thaw a frozen task
to handle OOM situation but a3201227f8 (freezer: make freezing() test
freeze conditions in effect instead of TIF_FREEZE) has reorganized the
code and stopped clearing freeze flag in __thaw_task. This means that
the target task only wakes up and goes into the fridge again because the
freezing condition hasn't changed for it. This reintroduces the bug
fixed by f660daac47.

Fix the issue by checking for TIF_MEMDIE thread flag in
freezing_slow_path and exclude the task from freezing completely. If a
task was already frozen it would get woken by __thaw_task from OOM killer
and get out of freezer after rechecking freezing().

Changes since v1
- put TIF_MEMDIE check into freezing_slowpath rather than in __refrigerator
  as per Oleg
- return __thaw_task into oom_scan_process_thread because
  oom_kill_process will not wake task in the fridge because it is
  sleeping uninterruptible

[mhocko@suse.cz: rewrote the changelog]
Fixes: a3201227f8 (freezer: make freezing() test freeze conditions in effect instead of TIF_FREEZE)
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:08 +00:00
Markos Chandras
28058a0bd1 MIPS: cp1emu: Fix ISA restrictions for cop1x_op instructions
commit a5466d7bba upstream.

Commit 08a07904e1 ("MIPS: math-emu: Remove most ifdefery") removed
the #ifdef ISA conditions and switched to runtime detection. However,
according to the instruction set manual, the cop1x_op instructions are
available in >=MIPS32r2 as well. This fixes a problem on MIPS32r2
with the ntpd package which failed to execute with a SIGILL exit code due
to the fact that a madd.d instruction was not being emulated.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Fixes: 08a07904e1 ("MIPS: math-emu: Remove most ifdefery")
Cc: linux-mips@linux-mips.org
Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/8173/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:08 +00:00
Daniel Borkmann
eb622aa247 random: add and use memzero_explicit() for clearing data
commit d4c5efdb97 upstream.

zatimend has reported that in his environment (3.16/gcc4.8.3/corei7)
memset() calls which clear out sensitive data in extract_{buf,entropy,
entropy_user}() in random driver are being optimized away by gcc.

Add a helper memzero_explicit() (similarly as explicit_bzero() variants)
that can be used in such cases where a variable with sensitive data is
being cleared out in the end. Other use cases might also be in crypto
code. [ I have put this into lib/string.c though, as it's always built-in
and doesn't need any dependencies then. ]

Fixes kernel bugzilla: 82041

Reported-by: zatimend@hotmail.co.uk
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
[ kamal: backport to 3.13-stable: one more memzero_explicit in extract_buf() ]
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:08 +00:00
Alex Deucher
5b67c018b8 drm/radeon: use gart memory for DMA ring tests
commit adfed2b058 upstream.

Avoids HDP cache flush issues when using vram which can
cause ring test failures on certain boards.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Alexander Fyodorov <halcy@yandex.ru>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:08 +00:00
Alex Deucher
e55f0fb3aa drm/radeon: fix speaker allocation setup
commit 4910403836 upstream.

If the sad_count is 0, set the hw to stereo and change
the error message to a warn.  A lot of monitors don't
set the speaker allocation block.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:07 +00:00
Darrick J. Wong
c6243bdb2f ext4: check s_chksum_driver when looking for bg csum presence
commit 813d32f913 upstream.

Convert the ext4_has_group_desc_csum predicate to look for a checksum
driver instead of the metadata_csum flag and change the bg checksum
calculation function to look for GDT_CSUM before taking the crc16
path.

Without this patch, if we mount with ^uninit_bg,^metadata_csum and
later metadata_csum gets turned on by accident, the block group
checksum functions will incorrectly assume that checksumming is
enabled (metadata_csum) but that crc16 should be used
(!s_chksum_driver).  This is totally wrong, so fix the predicate
and the checksum formula selection.

(Granted, if the metadata_csum feature bit gets enabled on a live FS
then something underhanded is going on, but we could at least avoid
writing garbage into the on-disk fields.)

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:07 +00:00
Vineet Gupta
1875434771 ARC: unbork FPU save/restore
commit 52e9bae938 upstream.

Fixes: 2ab402dfd6 "ARC: make start_thread() out-of-line"
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:07 +00:00
Anton Kolesov
bae99814ec ARC: Update order of registers in KGDB to match GDB 7.5
commit ebc0c74e76 upstream.

Order of registers has changed in GDB moving from 6.8 to 7.5. This patch
updates KGDB to work properly with GDB 7.5, though makes it incompatible
with 6.8.

Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:07 +00:00
Vineet Gupta
41e9866ee0 ARC: [nsimosci] Allow "headless" models to boot
commit 5c05483e2d upstream.

There are certain test configuration of virtual platform which don't
have any real console device (uart/pgu). So add tty0 as a fallback console
device to allow system to boot and be accessible via telnet

Otherwise with ttyS0 as only console, but 8250 disabled in kernel build,
init chokes.

Reported-by: Anton Kolesov <akolesov@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:06 +00:00
Dmitry Monakhov
f6770a16a9 ext4: move error report out of atomic context in ext4_init_block_bitmap()
commit aef4885ae1 upstream.

Error report likely result in IO so it is bad idea to do it from
atomic context.

This patch should fix following issue:

BUG: sleeping function called from invalid context at include/linux/buffer_head.h:349
in_atomic(): 1, irqs_disabled(): 0, pid: 137, name: kworker/u128:1
5 locks held by kworker/u128:1/137:
 #0:  ("writeback"){......}, at: [<ffffffff81085618>] process_one_work+0x228/0x4d0
 #1:  ((&(&wb->dwork)->work)){......}, at: [<ffffffff81085618>] process_one_work+0x228/0x4d0
 #2:  (jbd2_handle){......}, at: [<ffffffff81242622>] start_this_handle+0x712/0x7b0
 #3:  (&ei->i_data_sem){......}, at: [<ffffffff811fa387>] ext4_map_blocks+0x297/0x430
 #4:  (&(&bgl->locks[i].lock)->rlock){......}, at: [<ffffffff811f3180>] ext4_read_block_bitmap_nowait+0x5d0/0x630
CPU: 3 PID: 137 Comm: kworker/u128:1 Not tainted 3.17.0-rc2-00184-g82752e4 #165
Hardware name: Intel Corporation W2600CR/W2600CR, BIOS SE5C600.86B.99.99.x028.061320111235 06/13/2011
Workqueue: writeback bdi_writeback_workfn (flush-1:0)
 0000000000000411 ffff880813777288 ffffffff815c7fdc ffff880813777288
 ffff880813a8bba0 ffff8808137772a8 ffffffff8108fb30 ffff880803e01e38
 ffff880803e01e38 ffff8808137772c8 ffffffff811a8d53 ffff88080ecc6000
Call Trace:
 [<ffffffff815c7fdc>] dump_stack+0x51/0x6d
 [<ffffffff8108fb30>] __might_sleep+0xf0/0x100
 [<ffffffff811a8d53>] __sync_dirty_buffer+0x43/0xe0
 [<ffffffff811a8e03>] sync_dirty_buffer+0x13/0x20
 [<ffffffff8120f581>] ext4_commit_super+0x1d1/0x230
 [<ffffffff8120fa03>] save_error_info+0x23/0x30
 [<ffffffff8120fd06>] __ext4_error+0xb6/0xd0
 [<ffffffff8120f260>] ? ext4_group_desc_csum+0x140/0x190
 [<ffffffff811f2d8c>] ext4_read_block_bitmap_nowait+0x1dc/0x630
 [<ffffffff8122e23a>] ext4_mb_init_cache+0x21a/0x8f0
 [<ffffffff8113ae95>] ? lru_cache_add+0x55/0x60
 [<ffffffff8112e16c>] ? add_to_page_cache_lru+0x6c/0x80
 [<ffffffff8122eaa0>] ext4_mb_init_group+0x190/0x280
 [<ffffffff8122ec51>] ext4_mb_good_group+0xc1/0x190
 [<ffffffff8123309a>] ext4_mb_regular_allocator+0x17a/0x410
 [<ffffffff8122c821>] ? ext4_mb_use_preallocated+0x31/0x380
 [<ffffffff81233535>] ? ext4_mb_new_blocks+0x205/0x8e0
 [<ffffffff8116ed5c>] ? kmem_cache_alloc+0xfc/0x180
 [<ffffffff812335b0>] ext4_mb_new_blocks+0x280/0x8e0
 [<ffffffff8116f2c4>] ? __kmalloc+0x144/0x1c0
 [<ffffffff81221797>] ? ext4_find_extent+0x97/0x320
 [<ffffffff812257f4>] ext4_ext_map_blocks+0xbc4/0x1050
 [<ffffffff811fa387>] ? ext4_map_blocks+0x297/0x430
 [<ffffffff811fa3ab>] ext4_map_blocks+0x2bb/0x430
 [<ffffffff81200e43>] ? ext4_init_io_end+0x23/0x50
 [<ffffffff811feb44>] ext4_writepages+0x564/0xaf0
 [<ffffffff815cde3b>] ? _raw_spin_unlock+0x2b/0x40
 [<ffffffff810ac7bd>] ? lock_release_non_nested+0x2fd/0x3c0
 [<ffffffff811a009e>] ? writeback_sb_inodes+0x10e/0x490
 [<ffffffff811a009e>] ? writeback_sb_inodes+0x10e/0x490
 [<ffffffff811377e3>] do_writepages+0x23/0x40
 [<ffffffff8119c8ce>] __writeback_single_inode+0x9e/0x280
 [<ffffffff811a026b>] writeback_sb_inodes+0x2db/0x490
 [<ffffffff811a0664>] wb_writeback+0x174/0x2d0
 [<ffffffff810ac359>] ? lock_release_holdtime+0x29/0x190
 [<ffffffff811a0863>] wb_do_writeback+0xa3/0x200
 [<ffffffff811a0a40>] bdi_writeback_workfn+0x80/0x230
 [<ffffffff81085618>] ? process_one_work+0x228/0x4d0
 [<ffffffff810856cd>] process_one_work+0x2dd/0x4d0
 [<ffffffff81085618>] ? process_one_work+0x228/0x4d0
 [<ffffffff81085c1d>] worker_thread+0x35d/0x460
 [<ffffffff810858c0>] ? process_one_work+0x4d0/0x4d0
 [<ffffffff810858c0>] ? process_one_work+0x4d0/0x4d0
 [<ffffffff8108a885>] kthread+0xf5/0x100
 [<ffffffff810990e5>] ? local_clock+0x25/0x30
 [<ffffffff8108a790>] ? __init_kthread_worker+0x70/0x70
 [<ffffffff815ce2ac>] ret_from_fork+0x7c/0xb0
 [<ffffffff8108a790>] ? __init_kthread_work

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:06 +00:00
Dmitry Monakhov
10e55cd40d ext4: Replace open coded mdata csum feature to helper function
commit 9aa5d32ba2 upstream.

Besides the fact that this replacement improves code readability
it also protects from errors caused direct EXT4_S(sb)->s_es manipulation
which may result attempt to use uninitialized  csum machinery.

#Testcase_BEGIN
IMG=/dev/ram0
MNT=/mnt
mkfs.ext4 $IMG
mount $IMG $MNT
#Enable feature directly on disk, on mounted fs
tune2fs -O metadata_csum  $IMG
# Provoke metadata update, likey result in OOPS
touch $MNT/test
umount $MNT
#Testcase_END

# Replacement script
@@
expression E;
@@
- EXT4_HAS_RO_COMPAT_FEATURE(E, EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)
+ ext4_has_metadata_csum(E)

https://bugzilla.kernel.org/show_bug.cgi?id=82201

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:06 +00:00
Eric Sandeen
8035ac9178 ext4: fix reservation overflow in ext4_da_write_begin
commit 0ff8947fc5 upstream.

Delalloc write journal reservations only reserve 1 credit,
to update the inode if necessary.  However, it may happen
once in a filesystem's lifetime that a file will cross
the 2G threshold, and require the LARGE_FILE feature to
be set in the superblock as well, if it was not set already.

This overruns the transaction reservation, and can be
demonstrated simply on any ext4 filesystem without the LARGE_FILE
feature already set:

dd if=/dev/zero of=testfile bs=1 seek=2147483646 count=1 \
	conv=notrunc of=testfile
sync
dd if=/dev/zero of=testfile bs=1 seek=2147483647 count=1 \
	conv=notrunc of=testfile

leads to:

EXT4-fs: ext4_do_update_inode:4296: aborting transaction: error 28 in __ext4_handle_dirty_super
EXT4-fs error (device loop0) in ext4_do_update_inode:4301: error 28
EXT4-fs error (device loop0) in ext4_reserve_inode_write:4757: Readonly filesystem
EXT4-fs error (device loop0) in ext4_dirty_inode:4876: error 28
EXT4-fs error (device loop0) in ext4_da_write_end:2685: error 28

Adjust the number of credits based on whether the flag is
already set, and whether the current write may extend past the
LARGE_FILE limit.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:06 +00:00
Theodore Ts'o
ba55c5e8a3 ext4: add ext4_iget_normal() which is to be used for dir tree lookups
commit f4bb298102 upstream.

If there is a corrupted file system which has directory entries that
point at reserved, metadata inodes, prohibit them from being used by
treating them the same way we treat Boot Loader inodes --- that is,
mark them to be bad inodes.  This prohibits them from being opened,
deleted, or modified via chmod, chown, utimes, etc.

In particular, this prevents a corrupted file system which has a
directory entry which points at the journal inode from being deleted
and its blocks released, after which point Much Hilarity Ensues.

Reported-by: Sami Liedes <sami.liedes@iki.fi>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:05 +00:00
Theodore Ts'o
e1956e85e5 ext4: don't orphan or truncate the boot loader inode
commit e2bfb088fa upstream.

The boot loader inode (inode #5) should never be visible in the
directory hierarchy, but it's possible if the file system is corrupted
that there will be a directory entry that points at inode #5.  In
order to avoid accidentally trashing it, when such a directory inode
is opened, the inode will be marked as a bad inode, so that it's not
possible to modify (or read) the inode from userspace.

Unfortunately, when we unlink this (invalid/illegal) directory entry,
we will put the bad inode on the ophan list, and then when try to
unlink the directory, we don't actually remove the bad inode from the
orphan list before freeing in-memory inode structure.  This means the
in-memory orphan list is corrupted, leading to a kernel oops.

In addition, avoid truncating a bad inode in ext4_destroy_inode(),
since truncating the boot loader inode is not a smart thing to do.

Reported-by: Sami Liedes <sami.liedes@iki.fi>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:05 +00:00
Nicholas Bellinger
faed75ef56 iser-target: Disable TX completion interrupt coalescing
commit 0d0f660d88 upstream.

This patch explicitly disables TX completion interrupt coalescing logic
in isert_put_response() and isert_put_datain() that was originally added
as an efficiency optimization in commit 95b60f07.

It has been reported that this change can trigger ABORT_TASK timeouts
under certain small block workloads, where disabling coalescing was
required for stability.  According to Sagi, this doesn't impact
overall performance, so go ahead and disable it for now.

Reported-by: Moussa Ba <moussaba@micron.com>
Reported-by: Sagi Grimberg <sagig@dev.mellanox.co.il>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:05 +00:00
Nicholas Bellinger
7968b75538 target: Fix APTPL metadata handling for dynamic MappedLUNs
commit e24805637d upstream.

This patch fixes a bug in handling of SPC-3 PR Activate Persistence
across Target Power Loss (APTPL) logic where re-creation of state for
MappedLUNs from dynamically generated NodeACLs did not occur during
I_T Nexus establishment.

It adds the missing core_scsi3_check_aptpl_registration() call during
core_tpg_check_initiator_node_acl() -> core_tpg_add_node_to_devs() in
order to replay any pre-loaded APTPL metadata state associated with
the newly connected SCSI Initiator Port.

Cc: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:05 +00:00
Joern Engel
53f796334d qla_target: don't delete changed nacls
commit f4c24db1b7 upstream.

The code is currently riddled with "drop the hardware_lock to avoid a
deadlock" bugs that expose races.  One of those races seems to expose a
valid warning in tcm_qla2xxx_clear_nacl_from_fcport_map.  Add some
bandaid to it.

Signed-off-by: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:04 +00:00
Dmitry Monakhov
6f3df82794 ext4: grab missed write_count for EXT4_IOC_SWAP_BOOT
commit 3e67cfad22 upstream.

Otherwise this provokes complain like follows:
WARNING: CPU: 12 PID: 5795 at fs/ext4/ext4_jbd2.c:48 ext4_journal_check_start+0x4e/0xa0()
Modules linked in: brd iTCO_wdt lpc_ich mfd_core igb ptp dm_mirror dm_region_hash dm_log dm_mod
CPU: 12 PID: 5795 Comm: python Not tainted 3.17.0-rc2-00175-gae5344f #158
Hardware name: Intel Corporation W2600CR/W2600CR, BIOS SE5C600.86B.99.99.x028.061320111235 06/13/2011
 0000000000000030 ffff8808116cfd28 ffffffff815c7dfc 0000000000000030
 0000000000000000 ffff8808116cfd68 ffffffff8106ce8c ffff8808116cfdc8
 ffff880813b16000 ffff880806ad6ae8 ffffffff81202008 0000000000000000
Call Trace:
 [<ffffffff815c7dfc>] dump_stack+0x51/0x6d
 [<ffffffff8106ce8c>] warn_slowpath_common+0x8c/0xc0
 [<ffffffff81202008>] ? ext4_ioctl+0x9e8/0xeb0
 [<ffffffff8106ceda>] warn_slowpath_null+0x1a/0x20
 [<ffffffff8122867e>] ext4_journal_check_start+0x4e/0xa0
 [<ffffffff81228c10>] __ext4_journal_start_sb+0x90/0x110
 [<ffffffff81202008>] ext4_ioctl+0x9e8/0xeb0
 [<ffffffff8107b0bd>] ? ptrace_stop+0x24d/0x2f0
 [<ffffffff81088530>] ? alloc_pid+0x480/0x480
 [<ffffffff8107b1f2>] ? ptrace_do_notify+0x92/0xb0
 [<ffffffff81186545>] do_vfs_ioctl+0x4e5/0x550
 [<ffffffff815cdbcb>] ? _raw_spin_unlock_irq+0x2b/0x40
 [<ffffffff81186603>] SyS_ioctl+0x53/0x80
 [<ffffffff815ce2ce>] tracesys+0xd0/0xd5

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:04 +00:00
Jan Kara
6c49ff6fb4 ext4: fix mmap data corruption when blocksize < pagesize
commit d6320cbfc9 upstream.

Use truncate_isize_extended() when hole is being created in a file so that
->page_mkwrite() will get called for the partial tail page if it is
mmaped (see the first patch in the series for details).

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:04 +00:00
Jan Kara
c0552c087e vfs: fix data corruption when blocksize < pagesize for mmaped data
commit 90a8020278 upstream.

->page_mkwrite() is used by filesystems to allocate blocks under a page
which is becoming writeably mmapped in some process' address space. This
allows a filesystem to return a page fault if there is not enough space
available, user exceeds quota or similar problem happens, rather than
silently discarding data later when writepage is called.

However VFS fails to call ->page_mkwrite() in all the cases where
filesystems need it when blocksize < pagesize. For example when
blocksize = 1024, pagesize = 4096 the following is problematic:
  ftruncate(fd, 0);
  pwrite(fd, buf, 1024, 0);
  map = mmap(NULL, 1024, PROT_WRITE, MAP_SHARED, fd, 0);
  map[0] = 'a';       ----> page_mkwrite() for index 0 is called
  ftruncate(fd, 10000); /* or even pwrite(fd, buf, 1, 10000) */
  mremap(map, 1024, 10000, 0);
  map[4095] = 'a';    ----> no page_mkwrite() called

At the moment ->page_mkwrite() is called, filesystem can allocate only
one block for the page because i_size == 1024. Otherwise it would create
blocks beyond i_size which is generally undesirable. But later at
->writepage() time, we also need to store data at offset 4095 but we
don't have block allocated for it.

This patch introduces a helper function filesystems can use to have
->page_mkwrite() called at all the necessary moments.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-05 11:43:04 +00:00