Commit ee1de406ba ("random: simplify accounting logic") simplified
things too much, in that it allows the following to trigger an
overflow that results in a BUG_ON crash:
dd if=/dev/urandom of=/dev/zero bs=67108707 count=1
Thanks to Peter Zihlstra for discovering the crash, and Hannes
Frederic for analyizing the root cause.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Reported-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Greg Price <price@mit.edu>
The value written to PLLE_AUX was incorrect due to a wrong variable
being used. Without this fix SATA does not work.
Cc: stable@vger.kernel.org
Signed-off-by: Tuomas Tynkkynen <ttynkkynen@nvidia.com>
Tested-by: Mikko Perttunen <mperttunen@nvidia.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
[mturquette@linaro.org: improved changelog]
wdev->ifdev should be set by .change_virtual_intf(). This solves the
problem of WARN() messages on module unload.
Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 6ddeb6d844 (dmaengine: omap-dma: move IRQ handling to omap-dma)
added support for handling interrupts in the omap dmaengine driver
instead of the legacy driver. Because of different handling for
interrupts this however caused omap3 to hang eventually after hitting
off-idle.
Any of the virtual 32 DMA channels can be assigned to any of the
four DMA interrupts. So commit 6ddeb6d844 made the omap dmaengine
driver to use the second DMA interrupt while keeping the legacy code
still using the first DMA interrupt.
This means we need to save and restore both IRQENABLE_L1 in addition
to IRQENABLE_L0. As there is a chance that the DSP might be using
IRQENABLE_L2 or IRQENABLE_L3 lines, let's not touch those until
this has been confirmed. Let's just add a comment to the code for
now.
Fixes: 6ddeb6d844 (dmaengine: omap-dma: move IRQ handling to omap-dma)
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Commit c66d039197 broke NAND for non-DT boot on all OMAP2 and OMAP3
boards using board_nand_init(). Following error is seen at boot
[ 0.154998] (null): Unsupported NAND ECC scheme selected
For OMAP2 and OMAP3 platforms, the ecc_opt parameter in platform data
must be set to OMAP_ECC_HAM1_CODE_HW to work properly.
Tested on omap3-beagle c4.
Fixes: c66d039197 (mtd: nand: omap: combine different flavours of 1-bit hamming ecc schemes)
Cc: stable@vger.kernel.org # v3.12+
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
"choppy" audio playback on OMAP5. The other applies an OMAP3630 fix
for clock rate setting for camera to other OMAP3 chips.
Basic build, boot, and PM test results are available here:
http://www.pwsan.com/omap/testlogs/prcm-fixes-b-v3.15-rc/20140514112639/
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Merge tag 'for-v3.15-rc/omap-fixes-b' of git://git.kernel.org/pub/scm/linux/kernel/git/pjw/omap-pending into omap-for-v3.15/fixes-v3
Two small OMAP fixes for v3.15-rc. One fixes "slow motion" or
"choppy" audio playback on OMAP5. The other applies an OMAP3630 fix
for clock rate setting for camera to other OMAP3 chips.
Basic build, boot, and PM test results are available here:
http://www.pwsan.com/omap/testlogs/prcm-fixes-b-v3.15-rc/20140514112639/
Seems it helps some users, but causes issues for other users:
https://bugzilla.redhat.com/show_bug.cgi?id=1089545
So lets drop it for now until we've figured out a better fix.
Fixes: 43d9490244 (ACPI / video: Add use_native_backlight quirks for more systems)
References: https://bugzilla.redhat.com/show_bug.cgi?id=1089545
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Use a correct pipe type when filling un interrupt urbs. This should
finally take care of the WARN() messages on the console when USB urbs
are submitted.
Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit e2b149cc4b ("crush: add chooseleaf_vary_r tunable") added the
crush_map::chooseleaf_vary_r field but missed the decode part. This
lead to misdirected requests caused by incorrect raw crush mapping
sets.
Fixes: http://tracker.ceph.com/issues/8226
Reported-and-Tested-by: Dmitry Smirnov <onlyjob@member.fsf.org>
Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
It has been reported that using ZFSonLinux on rbd will result in memory
corruption. The bug report can be found here:
https://github.com/zfsonlinux/spl/issues/241http://tracker.ceph.com/issues/7790
The reason is that ZFS will send pages with page_count 0 into rbd, which in
turns send them to tcp_sendpage. However, tcp_sendpage cannot deal with
page_count 0, as it will do get_page and put_page, and erroneously free the
page.
This type of issue has been noted before, and handled in iscsi, drbd,
etc. So, rbd should also handle this. This fix address this issue by fall back
to slower sendmsg when page_count 0 detected.
Cc: Sage Weil <sage@inktank.com>
Cc: Yehuda Sadeh <yehuda@inktank.com>
Cc: stable@vger.kernel.org
Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Reviewed-by: Ilya Dryomov <ilya.dryomov@inktank.com>
The following happens when trying to run a kvm guest on a kernel
configured for 64k pages. This doesn't happen with 4k pages:
BUG: failure at include/linux/mm.h:297/put_page_testzero()!
Kernel panic - not syncing: BUG!
CPU: 2 PID: 4228 Comm: qemu-system-aar Tainted: GF 3.13.0-0.rc7.31.sa2.k32v1.aarch64.debug #1
Call trace:
[<fffffe0000096034>] dump_backtrace+0x0/0x16c
[<fffffe00000961b4>] show_stack+0x14/0x1c
[<fffffe000066e648>] dump_stack+0x84/0xb0
[<fffffe0000668678>] panic+0xf4/0x220
[<fffffe000018ec78>] free_reserved_area+0x0/0x110
[<fffffe000018edd8>] free_pages+0x50/0x88
[<fffffe00000a759c>] kvm_free_stage2_pgd+0x30/0x40
[<fffffe00000a5354>] kvm_arch_destroy_vm+0x18/0x44
[<fffffe00000a1854>] kvm_put_kvm+0xf0/0x184
[<fffffe00000a1938>] kvm_vm_release+0x10/0x1c
[<fffffe00001edc1c>] __fput+0xb0/0x288
[<fffffe00001ede4c>] ____fput+0xc/0x14
[<fffffe00000d5a2c>] task_work_run+0xa8/0x11c
[<fffffe0000095c14>] do_notify_resume+0x54/0x58
In arch/arm/kvm/mmu.c:unmap_range(), we end up doing an extra put_page()
on the stage2 pgd which leads to the BUG in put_page_testzero(). This
happens because a pud_huge() test in unmap_range() returns true when it
should always be false with 2-level pages tables used by 64k pages.
This patch removes support for huge puds if 2-level pagetables are
being used.
Signed-off-by: Mark Salter <msalter@redhat.com>
[catalin.marinas@arm.com: removed #ifndef around PUD_SIZE check]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: <stable@vger.kernel.org> # v3.11+
A few platforms lack a 'device_type = "memory"' for their memory
nodes, relying on an old ppc quirk in order to discover its memory.
Add the missing data so that all parsing code can find memory nodes
correctly.
Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: <stable@vger.kernel.org>
Acked-by: John Crispin <blogic@openwrt.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
The current .dts for ste-ccu8540 lacks a 'device_type = "memory"' for
its memory node, relying on an old ppc quirk in order to discover its
memory. Fix the data so that all parsing code can handle it correctly.
Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: devicetree@vger.kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Just like for pSCSI, if the transport sets get_write_cache, then it is
not valid to enable write cache emulation for it. Return an error.
see https://bugzilla.redhat.com/show_bug.cgi?id=1082675
Reviewed-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Andy Grover <agrover@redhat.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch explicitly disables Immediate + Unsolicited Data for ISER
connections during login in iscsi_login_zero_tsih_s2() when protection
has been enabled for the session by the underlying hardware.
This is currently required because protection / signature memory regions
(MRs) expect T10 PI to occur on RDMA READs + RDMA WRITEs transfers, and
not on a immediate data payload associated with ISCSI_OP_SCSI_CMD, or
unsolicited data-out associated with a ISCSI_OP_SCSI_DATA_OUT.
v2 changes:
- Add TARGET_PROT_DOUT_INSERT check (Sagi)
- Add pr_debug noisemaker (Sagi)
- Add goto to avoid early return from MRDSL check (nab)
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch fixes a free-after-use regression in ft_free_cmd(), where
ft_sess_put() is called with cmd->sess after percpu_ida_free() has
already released the tag.
Fix this bug by saving the ft_sess pointer ahead of percpu_ida_free(),
and pass it directly to ft_sess_put().
The regression was originally introduced in v3.13-rc1 commit:
commit 5f544cfac9
Author: Nicholas Bellinger <nab@daterainc.com>
Date: Mon Sep 23 12:12:42 2013 -0700
tcm_fc: Convert to per-cpu command map pre-allocation of ft_cmd
Reported-by: Jun Wu <jwu@stormojo.com>
Cc: Mark Rustad <mark.d.rustad@intel.com>
Cc: Robert Love <robert.w.love@intel.com>
Cc: <stable@vger.kernel.org> #3.13+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch changes an incorrect use of BUG_ON to instead generate a
REJECT + PROTOCOL_ERROR in iscsit_process_nop_out() code. This case
can occur with traditional TCP where a flood of zeros in the data
stream can reach this block for what is presumed to be a NOP-OUT with
a solicited reply, but without a valid iscsi_cmd pointer.
This incorrect BUG_ON was introduced during the v3.11-rc timeframe
with the following commit:
commit 778de36896
Author: Nicholas Bellinger <nab@linux-iscsi.org>
Date: Fri Jun 14 16:07:47 2013 -0700
iscsi/isert-target: Refactor ISCSI_OP_NOOP RX handling
Reported-by: Arshad Hussain <arshad.hussain@calsoftinc.com>
Cc: stable@vger.kernel.org # 3.11+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
When the target is in stop stage, iSER transport initiates RDMA disconnects.
The iSER initiator may wish to establish a new connection over the
still existing network portal. In this case iSER transport should not
accept and resume new RDMA connections. In order to learn that, iscsi_np
is added with enabled flag so the iSER transport can check when deciding
weather to accept and resume a new connection request.
The iscsi_np is enabled after successful transport setup, and disabled
before iscsi_np login threads are cleaned up.
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
RDMA CM and iSCSI target flows are asynchronous and completely
uncorrelated. Relying on the fact that iscsi_accept_np will be called
after CM connection request event and will wait for it is a mistake.
When attempting to login to a few targets this flow is racy and
unpredictable, but for parallel login to dozens of targets will
race and hang every time.
The correct synchronizing mechanism in this case is pending on
a semaphore rather than a wait_for_event. We keep the pending
interruptible for iscsi_np cleanup stage.
(Squash patch to remove dead code into parent - nab)
Reported-by: Slava Shwartsman <valyushash@gmail.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Should be adding list_add_tail($new, $head) and not
the other way around.
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Userspace tools assume if a value is read from configfs, it is valid
and will not cause an error if the same value is written back. The only
valid value for pi_prot_type for backends not supporting DIF is 0, so allow
this particular value to be set without returning an error.
Reported-by: Krzysztof Chojnowski <frirajder@gmail.com>
Signed-off-by: Andy Grover <agrover@redhat.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Cc: stable@vger.kernel.org # 3.14+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
The attached change significantly improves the performance of the LWS-CAS code
in syscall.S.
This allows a number of packages to build (e.g., zeromq3, gtest and libxs)
that previously failed because slow LWS-CAS performance under contention. In
particular, interrupts taken while the lock was taken degraded performance
significantly.
The change does the following:
1) Disables interrupts around the CAS operation, and
2) Changes the loads and stores to use the ordered completer, "o", on
PA 2.0. "o" and "ma" with a zero offset are equivalent. The latter is
accepted on both PA 1.X and 2.0.
The use of ordered loads and stores probably makes no difference on all
existing hardware, but it seemed pedantically correct. In particular, the CAS
operation must complete before LDCW lock is released. As written before, a
processor could reorder the operations.
I don't believe the period interrupts are disabled is long enough to
significantly increase interrupt latency. For example, the TLB insert code is
longer. Worst case is a memory fault in the CAS operation.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # 3.13+
Signed-off-by: Helge Deller <deller@gmx.de>
Ratelimit printing of userspace segfaults and make it runtime
configurable via the /proc/sys/debug/exception-trace variable. This
should resolve syslog from growing way too fast and thus prevents
possible system service attacks.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # 3.13+
When a new device is added below a hotplug bridge, the bridge's secondary
bus speed and the device's bus speed must match. The shpchp driver
previously checked the bridge's *primary* bus speed, not the secondary bus
speed.
This caused hot-add errors like:
shpchp 0000:00:03.0: Speed of bus ff and adapter 0 mismatch
Check the secondary bus speed instead.
[bhelgaas: changelog]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=75251
Fixes: 3749c51ac6 ("PCI: Make current and maximum bus speeds part of the PCI core")
Signed-off-by: Marcel Apfelbaum <marcel.a@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
CC: stable@vger.kernel.org # v2.6.34+
Make the CONFIG_OF=n prototpe of of_node_full_name() mateh the CONFIG_OF=y
version.
Fixes compile warnings like this:
sound/soc/soc-core.c: In function 'soc_check_aux_dev':
sound/soc/soc-core.c:1667:3: warning: passing argument 1 of 'of_node_full_name' discards 'const' qualifier from pointer target type [enabled by default]
codecname = of_node_full_name(aux_dev->codec_of_node);
when CONFIG_OF is not defined.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
* acpi-video:
ACPI / video: correct DMI tag for Dell Inspiron 7520
ACPI / video: Add use_native_backlight quirks for more systems
* acpi-blacklist:
ACPI / blacklist: Add dmi_enable_osi_linux quirk for Asus EEE PC 1015PX
ACPI: blacklist win8 OSI for Dell Inspiron 7737
* acpi-ac:
ACPI: Revert "ACPI / AC: convert ACPI ac driver to platform bus"
* acpi-proc:
ACPI / proc: Do not say when /proc interfaces will be deleted in Kconfig
ACPI: Revert "ACPI / Battery: Remove battery's proc directory"
ACPI: Revert "ACPI: Remove CONFIG_ACPI_PROCFS_POWER and cm_sbsc.c"
* acpica:
ACPICA: Tables: Restore old behavor to favor 32-bit FADT addresses.
ACPICA: Tables: Fix invalid pointer accesses in acpi_tb_parse_root_table().
* acpi-tpm:
ACPI / TPM: Fix resume regression on Chromebooks
* acpi-processor:
ACPI / processor: do not mark present at boot but not onlined CPU as onlined
On SNB the BIOS provided WM memory latency values seem insufficient to
handle high resolution displays.
In this particular case the display mode was a 2560x1440@60Hz, which
makes the pixel clock 241.5 MHz. It was empirically found that a memory
latency value if 1.2 usec is enough to avoid underruns, whereas the BIOS
provided value of 0.7 usec was clearly too low. Incidentally 1.2 usec
is what the typical BIOS provided values are on IVB systems.
Increase the WM memory latency values to at least 1.2 usec on SNB.
Hopefully this won't have a significant effect on power consumption.
v2: Increase the latency values regardless of the pixel clock
Cc: Robert N <crshman@gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=70254
Tested-by: Robert Navarro <crshman@gmail.com>
Tested-by: Vitaly Minko <vitaly.minko@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
When we set backlight on behalf of ACPI opregion, we will convert the
backlight value in the 0-255 range defined in opregion to the actual
hardware level. Commit 22505b82a2 (drm/i915: avoid brightness overflow
when doing scale) is meant to fix the overflow problem when doing the
conversion, but it also caused a problem that the converted hardware
level doesn't quite represent the intended value: say user wants maximum
backlight level(255 in opregion's range), then we will calculate the
actual hardware level to be: level = freq / max * level, where freq is
the hardware's max backlight level(937 on an user's box), and max and
level are all 255. The converted value should be 937 but the above
calculation will yield 765.
To fix this issue, just use 64 bits to do the calculation to keep the
precision and avoid overflow at the same time.
Buglink: https://bugzilla.kernel.org/show_bug.cgi?id=72491
Reported-by: Nico Schottelius <nico-bugzilla.kernel.org@schottelius.org>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@vger.kernel.org
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
This matches the algorithm used by earlier kernels when selecting the
mode for the fbcon. And only if there is no modes at all, do we fall
back to using the BIOS configuration. Seamless transition is still
preserved (from the BIOS configuration to ours) so long as the BIOS has
also chosen what we hope is the native configuration.
Reported-by: Knut Petersen <Knut_Petersen@t-online.de>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=78655
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Tested-by: Knut Petersen <Knut_Petersen@t-online.de>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
[Jani: applied Chris' "Please imagine that I wrote this correctly."]
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
There are certain BDW high res eDP machines that regressed due to
commit 38aecea0cc
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Mon Mar 3 11:18:10 2014 +0100
drm/i915: reverse dp link param selection, prefer fast over wide again
The commit lead to 2 lanes at 5.4 Gbps being used instead of 4 lanes at
2.7 Gbps on the affected machines. Link training succeeded for both, but
the screen remained blank with the former config. Further investigation
showed that 4 lanes at 5.4 Gbps worked also.
The root cause for the blank screen using 2 lanes remains unknown, but
apparently the driver for a certain other operating system by default
uses the max available lanes. Follow suit on Broadwell eDP, for at least
until we figure out what is going on.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=76711
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Tested-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Checkin:
b3b42ac2cb x86-64, modify_ldt: Ban 16-bit segments on 64-bit kernels
disabled 16-bit segments on 64-bit kernels due to an information
leak. However, it does seem that people are genuinely using Wine to
run old 16-bit Windows programs on Linux.
A proper fix for this ("espfix64") is coming in the upcoming merge
window, but as a temporary fix, create a sysctl to allow the
administrator to re-enable support for 16-bit segments.
It adds a "/proc/sys/abi/ldt16" sysctl that defaults to zero (off). If
you hit this issue and care about your old Windows program more than
you care about a kernel stack address information leak, you can do
echo 1 > /proc/sys/abi/ldt16
as root (add it to your startup scripts), and you should be ok.
The sysctl table is only added if you have COMPAT support enabled on
x86-64, but I assume anybody who runs old windows binaries very much
does that ;)
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/CA%2B55aFw9BPoD10U1LfHbOMpHWZkvJTkMcfCs9s3urPr1YyWBxw@mail.gmail.com
Cc: <stable@vger.kernel.org>
_STK_LIM_MAX could be used to override the RLIMIT_STACK hard limit from
an arch's include/uapi/asm-generic/resource.h file, but is no longer
used since both parisc and metag removed the override. Therefore remove
it entirely, setting the hard RLIMIT_STACK limit to RLIM_INFINITY
directly in include/asm-generic/resource.h.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-arch@vger.kernel.org
Cc: Helge Deller <deller@gmx.de>
Cc: John David Anglin <dave.anglin@bell.net>
Meta overrode _STK_LIM_MAX (the default RLIMIT_STACK hard limit) to
256MB, apparently in an attempt to prevent setup_arg_pages's
STACK_GROWSUP code from choosing the maximum stack size of 1GB, which is
far too large for Meta's limited virtual address space and hits a BUG_ON
(stack_top is usually 0x3ffff000).
However the commit "metag: Reduce maximum stack size to 256MB" reduces
the absolute stack size limit to a safe value for metag. This allows the
default _STK_LIM_MAX override to be removed, bringing the default
behaviour in line with all other architectures. Parisc in particular
recently removed their override of _STK_LIMT_MAX in commit e0d8898d76
(parisc: remove _STK_LIM_MAX override) since it subtly affects stack
allocation semantics in userland. Meta's uapi/asm/resource.h can now be
removed and switch to using generic-y.
Suggested-by: Helge Deller <deller@gmx.de>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Cc: John David Anglin <dave.anglin@bell.net>
And we don't invert it properly when initialising the dquot lru
list.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Invert it.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
And it should be negative.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This patch affects only architectures where the stack grows upwards
(currently parisc and metag only). On those do not hardcode the maximum
initial stack size to 1GB for 32-bit processes, but make it configurable
via a config option.
The main problem with the hardcoded stack size is, that we have two
memory regions which grow upwards: stack and heap. To keep most of the
memory available for heap in a flexmap memory layout, it makes no sense
to hard allocate up to 1GB of the memory for stack which can't be used
as heap then.
This patch makes the stack size for 32-bit processes configurable and
uses 80MB as default value which has been in use during the last few
years on parisc and which hasn't showed any problems yet.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: linux-parisc@vger.kernel.org
Cc: linux-metag@vger.kernel.org
Cc: John David Anglin <dave.anglin@bell.net>
Specify the maximum stack size for arches where the stack grows upward
(parisc and metag) in asm/processor.h rather than hard coding in
fs/exec.c so that metag can specify a smaller value of 256MB rather than
1GB.
This fixes a BUG on metag if the RLIMIT_STACK hard limit is increased
beyond a safe value by root. E.g. when starting a process after running
"ulimit -H -s unlimited" it will then attempt to use a stack size of the
maximum 1GB which is far too big for metag's limited user virtual
address space (stack_top is usually 0x3ffff000):
BUG: failure at fs/exec.c:589/shift_arg_pages()!
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: linux-parisc@vger.kernel.org
Cc: linux-metag@vger.kernel.org
Cc: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # only needed for >= v3.9 (arch/metag)
Volatile access doesn't really imply the compiler barrier. Volatile access
is only ordered with respect to other volatile accesses, it isn't ordered
with respect to general memory accesses. Gcc may reorder memory accesses
around volatile access, as we can see in this simple example (if we
compile it with optimization, both increments of *b will be collapsed to
just one):
void fn(volatile int *a, long *b)
{
(*b)++;
*a = 10;
(*b)++;
}
Consequently, we need the compiler barrier after a write to the volatile
variable, to make sure that the compiler doesn't reorder the volatile
write with something else.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Commit 3e9f1be1b4 ("dm mpath: remove process_queued_ios()") did not
consistently take the multipath device's spinlock (m->lock) before
calling dm_table_run_md_queue_async() -- which takes the q->queue_lock.
Found with code inspection using hint from reported lockdep warning.
Reported-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
