linux/include, branch v2.6.27.46

KVM: VMX: Check cpl before emulating debug register access

2010-04-01T22:52:24Z

commit 0a79b009525b160081d75cef5dbf45817956acf2 upstream. Debug registers may only be accessed from cpl 0. Unfortunately, vmx will code to emulate the instruction even though it was issued from guest userspace, possibly leading to an unexpected trap later. Signed-off-by: Avi Kivity Signed-off-by: Marcelo Tosatti Signed-off-by: Greg Kroah-Hartman

KVM: x86 emulator: limit instructions to 15 bytes

2010-04-01T22:52:23Z

commit eb3c79e64a70fb8f7473e30fa07e89c1ecc2c9bb upstream [ : backport to 2.6.27 ] While we are never normally passed an instruction that exceeds 15 bytes, smp games can cause us to attempt to interpret one, which will cause large latencies in non-preempt hosts. Signed-off-by: Avi Kivity Signed-off-by: Greg Kroah-Hartman

sched: wakeup preempt when small overlap

2010-04-01T22:52:21Z

commit 15afe09bf496ae10c989e1a375a6b5da7bd3e16e upstream. Lin Ming reported a 10% OLTP regression against 2.6.27-rc4. The difference seems to come from different preemption agressiveness, which affects the cache footprint of the workload and its effective cache trashing. Aggresively preempt a task if its avg overlap is very small, this should avoid the task going to sleep and find it still running when we schedule back to it - saving a wakeup. Reported-by: Lin Ming Signed-off-by: Peter Zijlstra Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

sched: fine-tune SD_SIBLING_INIT

2010-04-01T22:52:20Z

commit 52c642f33b14bfa1b00ef2b68296effb34a573f3 upstream. fine-tune the HT sched-domains parameters as well. On a HT capable box, this increases lat_ctx performance from 23.87 usecs to 1.49 usecs: # before $ ./lat_ctx -s 0 2 "size=0k ovr=1.89 2 23.87 # after $ ./lat_ctx -s 0 2 "size=0k ovr=1.84 2 1.49 Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

sched: fine-tune SD_MC_INIT

2010-04-01T22:52:20Z

commit 14800984706bf6936bbec5187f736e928be5c218 upstream. Tune SD_MC_INIT the same way as SD_CPU_INIT: unset SD_BALANCE_NEWIDLE, and set SD_WAKE_BALANCE. This improves vmark by 5%: vmark 132102 125968 125497 messages/sec avg 127855.66 .984 vmark 139404 131719 131272 messages/sec avg 134131.66 1.033 Signed-off-by: Mike Galbraith Acked-by: Peter Zijlstra Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

x86: fix csum_ipv6_magic asm memory clobber

2010-04-01T22:52:19Z

commit 392d814daf460a9564d29b2cebc51e1ea34e0504 upstream. Just like ip_fast_csum, the assembly snippet in csum_ipv6_magic needs a memory clobber, as it is only passed the address of the buffer, not a memory reference to the buffer itself. This caused failures in Hurd's pfinetv4 when we tried to compile it with gcc-4.3 (bogus checksums). Signed-off-by: Samuel Thibault Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Acked-by: "David S. Miller" Cc: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

resource: add helpers for fetching rlimits

2010-04-01T22:52:17Z

commit 3e10e716abf3c71bdb5d86b8f507f9e72236c9cd upstream. We want to be sure that compiler fetches the limit variable only once, so add helpers for fetching current and maximal resource limits which do that. Add them to sched.h (instead of resource.h) due to circular dependency sched.h->resource.h->task_struct Alternative would be to create a separate res_access.h or similar. Signed-off-by: Jiri Slaby Cc: James Morris Cc: Heiko Carstens Cc: Andrew Morton Cc: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

ipv6: reassembly: use seperate reassembly queues for conntrack and local delivery

2010-01-06T23:17:14Z

commit 0b5ccb2ee250136dd7385b1c7da28417d0d4d32d upstream. Currently the same reassembly queue might be used for packets reassembled by conntrack in different positions in the stack (PREROUTING/LOCAL_OUT), as well as local delivery. This can cause "packet jumps" when the fragment completing a reassembled packet is queued from a different position in the stack than the previous ones. Add a "user" identifier to the reassembly queue key to seperate the queues of each caller, similar to what we do for IPv4. Signed-off-by: Patrick McHardy Signed-off-by: Greg Kroah-Hartman

signal: Fix alternate signal stack check

2009-12-18T21:30:40Z

commit 2a855dd01bc1539111adb7233f587c5c468732ac upstream. All architectures in the kernel increment/decrement the stack pointer before storing values on the stack. On architectures which have the stack grow down sas_ss_sp == sp is not on the alternate signal stack while sas_ss_sp + sas_ss_size == sp is on the alternate signal stack. On architectures which have the stack grow up sas_ss_sp == sp is on the alternate signal stack while sas_ss_sp + sas_ss_size == sp is not on the alternate signal stack. The current implementation fails for architectures which have the stack grow down on the corner case where sas_ss_sp == sp.This was reported as Debian bug #544905 on AMD64. Simplified test case: http://download.breakpoint.cc/tc-sig-stack.c The test case creates the following stack scenario: 0xn0300 stack top 0xn0200 alt stack pointer top (when switching to alt stack) 0xn01ff alt stack end 0xn0100 alt stack start == stack pointer If the signal is sent the stack pointer is pointing to the base address of the alt stack and the kernel erroneously decides that it has already switched to the alternate stack because of the current check for "sp - sas_ss_sp < sas_ss_size" On parisc (stack grows up) the scenario would be: 0xn0200 stack pointer 0xn01ff alt stack end 0xn0100 alt stack start = alt stack pointer base (when switching to alt stack) 0xn0000 stack base This is handled correctly by the current implementation. [ tglx: Modified for archs which have the stack grow up (parisc) which would fail with the correct implementation for stack grows down. Added a check for sp >= current->sas_ss_sp which is strictly not necessary but makes the code symetric for both variants ] Signed-off-by: Sebastian Andrzej Siewior Cc: Oleg Nesterov Cc: Roland McGrath Cc: Kyle McMartin LKML-Reference: <20091025143758.GA6653@Chamillionaire.breakpoint.cc> Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

USB: usb-serial: replace shutdown with disconnect, release

2009-12-08T19:17:31Z

This is commit f9c99bb8b3a1ec81af68d484a551307326c2e933 back-ported to 2.6.27.39. This patch (as1254-2) splits up the shutdown method of usb_serial_driver into a disconnect and a release method. The problem is that the usb-serial core was calling shutdown during disconnect handling, but drivers didn't expect it to be called until after all the open file references had been closed. The result was an oops when the close method tried to use memory that had been deallocated by shutdown. Signed-off-by: Alan Stern Tested-by: Rory Filer Signed-off-by: Greg Kroah-Hartman