This patch fixes the regression in functionality where the
kernel debugger and the perf API do not nicely share hw
breakpoint reservations.
The kernel debugger cannot use any mutex_lock() calls because it
can start the kernel running from an invalid context.
A mutex free version of the reservation API needed to get
created for the kernel debugger to safely update hw breakpoint
reservations.
The possibility for a breakpoint reservation to be concurrently
processed at the time that kgdb interrupts the system is
improbable. Should this corner case occur the end user is
warned, and the kernel debugger will prohibit updating the
hardware breakpoint reservations.
Any time the kernel debugger reserves a hardware breakpoint it
will be a system wide reservation.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: kgdb-bugreport@lists.sourceforge.net
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: torvalds@linux-foundation.org
LKML-Reference: <1264719883-7285-3-git-send-email-jason.wessel@windriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In the 2.6.33 kernel, the hw_breakpoint API is now used for the
performance event counters. The hw_breakpoint_handler() now
consumes the hw breakpoints that were previously set by kgdb
arch specific code. In order for kgdb to work in conjunction
with this core API change, kgdb must use some of the low level
functions of the hw_breakpoint API to install, uninstall, and
deal with hw breakpoint reservations.
The kgdb core required a change to call kgdb_disable_hw_debug
anytime a slave cpu enters kgdb_wait() in order to keep all the
hw breakpoints in sync as well as to prevent hitting a hw
breakpoint while kgdb is active.
During the architecture specific initialization of kgdb, it will
pre-allocate 4 disabled (struct perf event **) structures. Kgdb
will use these to manage the capabilities for the 4 hw
breakpoint registers, per cpu. Right now the hw_breakpoint API
does not have a way to ask how many breakpoints are available,
on each CPU so it is possible that the install of a breakpoint
might fail when kgdb restores the system to the run state. The
intent of this patch is to first get the basic functionality of
hw breakpoints working and leave it to the person debugging the
kernel to understand what hw breakpoints are in use and what
restrictions have been imposed as a result. Breakpoint
constraints will be dealt with in a future patch.
While atomic, the x86 specific kgdb code will call
arch_uninstall_hw_breakpoint() and arch_install_hw_breakpoint()
to manage the cpu specific hw breakpoints.
The net result of these changes allow kgdb to use the same pool
of hw_breakpoints that are used by the perf event API, but
neither knows about future reservations for the available hw
breakpoint slots.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: kgdb-bugreport@lists.sourceforge.net
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: torvalds@linux-foundation.org
LKML-Reference: <1264719883-7285-2-git-send-email-jason.wessel@windriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
On a given architecture, when hardware breakpoint registration fails
due to un-supported access type (read/write/execute), we lose the bp
slot since register_perf_hw_breakpoint() does not release the bp slot
on failure.
Hence, any subsequent hardware breakpoint registration starts failing
with 'no space left on device' error.
This patch introduces error handling in register_perf_hw_breakpoint()
function and releases bp slot on error.
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: K. Prasad <prasad@linux.vnet.ibm.com>
Cc: Maneesh Soni <maneesh@in.ibm.com>
LKML-Reference: <20100121125516.GA32521@in.ibm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: Drop EXT4_GET_BLOCKS_UPDATE_RESERVE_SPACE flag
ext4: Fix quota accounting error with fallocate
ext4: Handle -EDQUOT error on write
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
ASoC: fix a memory-leak in wm8903
ALSA: hda - add possibility to choose speakers configuration for 4930g
ALSA: hda - Fix HP T5735 automute
ALSA: hda - Turn on EAPD only if available for Realtek codecs
ALSA: hda - Fix parsing pin node 0x21 on ALC259
* 'kvm-updates/2.6.33' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86: Fix leak of free lapic date in kvm_arch_vcpu_init()
KVM: x86: Fix probable memory leak of vcpu->arch.mce_banks
KVM: S390: fix potential array overrun in intercept handling
KVM: fix spurious interrupt with irqfd
eventfd - allow atomic read and waitqueue remove
KVM: MMU: bail out pagewalk on kvm_read_guest error
KVM: properly check max PIC pin in irq route setup
KVM: only allow one gsi per fd
KVM: x86: Fix host_mapping_level()
KVM: powerpc: Show timing option only on embedded
KVM: Fix race between APIC TMR and IRR
* 'linux-next' of git://git.infradead.org/ubi-2.6:
UBI: fix memory leak in update path
UBI: add more checks to chdev open
UBI: initialise update marker
* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
hwmon: (fschmd) Fix a memleak on multiple opens of /dev/watchdog
hwmon: (asus_atk0110) Do not fail if MBIF is missing
hwmon: (amc6821) Double unlock bug
hwmon: (smsc47m1) Fix section mismatch
* 'drm-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: (95 commits)
drm/radeon/kms: preface warning printk with driver name
drm/radeon/kms: drop unnecessary printks.
drm: fix regression in fb blank handling
drm/radeon/kms: make hibernate work on IGPs
drm/vmwgfx: Optimize memory footprint for DMA buffers.
drm/ttm: Allow system memory as a busy placement.
drm/ttm: Fix race condition in ttm_bo_delayed_delete (v3, final)
drm/nv50: prevent switching off SOR when in use for DVI-over-DP
drm/nv50: fail auxch transaction if reply count not what we expect
drm/nouveau: fix failure path if userspace specifies no valid memtypes
drm/nouveau: report LVDS as disconnected if lid closed
drm/radeon/kms: fix legacy get_engine/memory clock
drm/radeon/kms/atom: atom parser fixes
drm/radeon/kms: clean up atombios pll code
drm/radeon/kms: clean up pll struct
drm/radeon/kms/atom: fix crtc lock ordering
drm/radeon: r6xx/r7xx possible security issue, system ram access
drm/radeon/kms: r600/r700 don't test ib if ib initialization fails
drm/radeon/kms: Forbid creation of framebuffer with no valid GEM object
drm/radeon/kms: r600 handle irq vector ring overflow
...
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (42 commits)
virtio_net: Make delayed refill more reliable
sfc: Use fixed-size buffers for MCDI NVRAM requests
sfc: Add workspace for GMAC bug workaround to MCDI MAC_STATS buffer
tcp_probe: avoid modulus operation and wrap fix
qlge: Only free resources if they were allocated
netns xfrm: deal with dst entries in netns
sky2: revert config space change
vlan: fix vlan_skb_recv()
netns xfrm: fix "ip xfrm state|policy count" misreport
sky2: Enable/disable WOL per hardware device
net: Fix IPv6 GSO type checks in Intel ethernet drivers
igb/igbvf: cleanup exception handling in tx_map_adv
MAINTAINERS: Add Intel igbvf maintainer
e1000/e1000e: don't use small hardware rx buffers
fmvj18x_cs: add new id (Panasonic lan & modem card)
be2net: swap only first 2 fields of mcc_wrb
Please add support for Microsoft MN-120 PCMCIA network card
be2net: fix bug in rx page posting
wimax/i2400m: Add support for more i6x50 SKUs
e1000e: enhance frame fragment detection
...
* 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6: (25 commits)
OMAP2/3: DMTIMER: Clear pending interrupts when stopping a timer
PM debug: Fix warning when no CONFIG_DEBUG_FS
OMAP3: PM: DSS PM_WKEN to refill DMA
OMAP: timekeeping: time should not stop during suspend
OMAP3: PM: Force write last pad config register into save area
OMAP: omap3_pm_get_suspend_state() error ignored in pwrdm_suspend_get()
OMAP3: PM: Enable wake-up from McBSP2, 3 and 4 modules
OMAP3: PM debug: fix build error when !CONFIG_DEBUG_FS
OMAP3: PM: Removing redundant and potentially dangerous PRCM configration
OMAP3: Fixed ARM aux ctrl register save/restore
OMAP3: CPUidle: Fixed timer resolution
OMAP3: PM: Remove duplicate code blocks
OMAP3: PM: Disable interrupt controller AUTOIDLE before WFI
OMAP3: PM: Enable system control module autoidle
OMAP3: PM: Ack pending interrupts before entering suspend
omap: Enable GPMC clock in gpmc_init
OMAP1 clock: fix for "BUG: spinlock lockup on CPU#0"
OMAP4: clocks: Fix the clksel_rate struct DPLL divs
OMAP4: PRCM: Fix the base address for CHIRONSS reg defines
OMAP: dma_chan[lch_head].flag & OMAP_DMA_ACTIVE tested twice in omap_dma_unlink_lch()
...
I have seen RX stalls on a machine that experienced a suspected
OOM. After the stall, the RX buffer is empty on the guest side
and there are exactly 16 entries available on the host side. As
the number of entries is less than that required by a maximal
skb, the host cannot proceed.
The guest did not have a refill job scheduled.
My diagnosis is that an OOM had occured, with the delayed refill
job scheduled. The job was able to allocate at least one skb, but
not enough to overcome the minimum required by the host to proceed.
As the refill job would only reschedule itself if it failed completely
to allocate any skbs, this would lead to an RX stall.
The following patch removes this stall possibility by always
rescheduling the refill job until the ring is totally refilled.
Testing has shown that the RX stall no longer occurs whereas
previously it would occur within a day.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The low-level MCDI code always uses 32-bit MMIO operations, and
callers must pad input and output buffers to multiples of 4 bytes.
The MCDI NVRAM functions are not doing this. Also, their buffers are
declared as variable-length arrays with no explicit maximum length.
Switch to a fixed buffer size based on the chunk size used by the
MTD driver (which is a multiple of 4).
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Due to a hardware bug in the SFC9000 family, the firmware must
transfer raw GMAC statistics to host memory before aggregating them
into the cooked (speed-independent) MAC statistics. Extend the stats
buffer to support this.
The length of the buffer is explicit in the MAC_STATS command, so this
change is backward-compatible on both sides.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
By rounding up the buffer size to power of 2, several expensive
modulus operations can be avoided. This patch also solves a bug where
the gap need when ring gets full was not being accounted for.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently qlge tries to release regions even if they were not allocated.
This causes messages like the following in the kernel log
Trying to free nonexistent resource <00000000006af400-00000000006af4ff>
Trying to free nonexistent resource <00003c04ff9f4000-00003c04ff9f7fff>
Trying to free nonexistent resource <00003c04ffc00000-00003c04ffcfffff>
This patch fixes the goto logic in order to not release the resources
if they were not allocated.
Signed-off-by: Breno Leitao <leitao@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The mdelay function was used between I/O access commands, that causes peak
in CPU usage. Fix it by substitution mdelay to msleep.
Expand usage on fitPC2 compatible boards according to DMI identification.
Signed-off-by: Denis Turischev <denis@compulab.co.il>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
In function kvm_arch_vcpu_init(), if the memory malloc for
vcpu->arch.mce_banks is fail, it does not free the memory
of lapic date. This patch fixed it.
Cc: stable@kernel.org
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Jason Wessel
Mahesh Salgaonkar
Amerigo Wang
Yong Wang
Greg Kroah-Hartman
Linus Torvalds
Herbert Xu
Ben Hutchings
Guido Barzini
Stephen Hemminger
Breno Leitao
Denis Turischev
Takashi Iwai
Guennadi Liakhovetski
Wei Yongjun