linux-toradex.git/arch, branch v3.4.23

x86, fpu: Avoid FPU lazy restore after suspend

2012-12-10T18:59:39+00:00

commit 644c154186386bb1fa6446bc5e037b9ed098db46 upstream.

When a cpu enters S3 state, the FPU state is lost.
After resuming for S3, if we try to lazy restore the FPU for a process running
on the same CPU, this will result in a corrupted FPU context.

Ensure that "fpu_owner_task" is properly invalided when (re-)initializing a CPU,
so nobody will try to lazy restore a state which doesn't exist in the hardware.

Tested with a 64-bit kernel on a 4-core Ivybridge CPU with eagerfpu=off,
by doing thousands of suspend/resume cycles with 4 processes doing FPU
operations running. Without the patch, a process is killed after a
few hundreds cycles by a SIGFPE.

Signed-off-by: Vincent Palatin 
Cc: Duncan Laurie 
Cc: Olof Johansson 
Link: http://lkml.kernel.org/r/1354306532-1014-1-git-send-email-vpalatin@chromium.org
Signed-off-by: H. Peter Anvin 
Signed-off-by: Greg Kroah-Hartman

ARM: Kirkwood: Update PCI-E fixup

2012-12-10T18:59:39+00:00

commit 1dc831bf53fddcc6443f74a39e72db5bcea4f15d upstream.

- The code relies on rc_pci_fixup being called, which only happens
  when CONFIG_PCI_QUIRKS is enabled, so add that to Kconfig. Omitting
  this causes a booting failure with a non-obvious cause.
- Update rc_pci_fixup to set the class properly, copying the
  more modern style from other places
- Correct the rc_pci_fixup comment

Signed-off-by: Jason Gunthorpe 
Signed-off-by: Jason Cooper 
Signed-off-by: Greg Kroah-Hartman

Dove: Fix irq_to_pmu()

2012-12-10T18:59:38+00:00

commit d356cf5a74afa32b40decca3c9dd88bc3cd63eb5 upstream.

PMU interrupts start at IRQ_DOVE_PMU_START, not IRQ_DOVE_PMU_START + 1.
Fix the condition.  (It may have been less likely to occur had the code
been written "if (irq >= IRQ_DOVE_PMU_START" which imho is the easier
to understand notation, and matches the normal way of thinking about
these things.)

Signed-off-by: Russell King 
Signed-off-by: Jason Cooper 
Signed-off-by: Greg Kroah-Hartman

Dove: Attempt to fix PMU/RTC interrupts

2012-12-10T18:59:38+00:00

commit 5d3df935426271016b895aecaa247101b4bfa35e upstream.

Fix the acknowledgement of PMU interrupts on Dove: some Dove hardware
has not been sensibly designed so that interrupts can be handled in a
race free manner.  The PMU is one such instance.

The pending (aka 'cause') register is a bunch of RW bits, meaning that
these bits can be both cleared and set by software (confirmed on the
Armada-510 on the cubox.)

Hardware sets the appropriate bit when an interrupt is asserted, and
software is required to clear the bits which are to be processed.  If
we write ~(1 << bit), then we end up asserting every other interrupt
except the one we're processing.  So, we need to do a read-modify-write
cycle to clear the asserted bit.

However, any interrupts which occur in the middle of this cycle will
also be written back as zero, which will also clear the new interrupts.

The upshot of this is: there is _no_ way to safely clear down interrupts
in this register (and other similarly behaving interrupt pending
registers on this device.)  The patch below at least stops us creating
new interrupts.

Signed-off-by: Russell King 
Signed-off-by: Jason Cooper 
Signed-off-by: Greg Kroah-Hartman

x86-32: Export kernel_stack_pointer() for modules

2012-12-06T02:38:34+00:00

commit cb57a2b4cff7edf2a4e32c0163200e9434807e0a upstream.

Modules, in particular oprofile (and possibly other similar tools)
need kernel_stack_pointer(), so export it using EXPORT_SYMBOL_GPL().

Cc: Yang Wei 
Cc: Robert Richter 
Cc: Jun Zhang 
Link: http://lkml.kernel.org/r/20120912135059.GZ8285@erda.amd.com
Signed-off-by: H. Peter Anvin 
Cc: Robert Richter 
Cc: Herton Ronaldo Krzesinski 
Cc: Philip Müller 
Signed-off-by: Greg Kroah-Hartman

ARM: OMAP: counter: add locking to read_persistent_clock

2012-12-03T19:47:23+00:00

commit 9d7d6e363b06934221b81a859d509844c97380df upstream.

read_persistent_clock uses a global variable, use a spinlock to
ensure non-atomic updates to the variable don't overlap and cause
time to move backwards.

Signed-off-by: Colin Cross 
Signed-off-by: R Sricharan 
Signed-off-by: Tony Lindgren 
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

powerpc/eeh: Lock module while handling EEH event

2012-12-03T19:47:23+00:00

commit feadf7c0a1a7c08c74bebb4a13b755f8c40e3bbc upstream.

The EEH core is talking with the PCI device driver to determine the
action (purely reset, or PCI device removal). During the period, the
driver might be unloaded and in turn causes kernel crash as follows:

EEH: Detected PCI bus error on PHB#4-PE#10000
EEH: This PCI device has failed 3 times in the last hour
lpfc 0004:01:00.0: 0:2710 PCI channel disable preparing for reset
Unable to handle kernel paging request for data at address 0x00000490
Faulting instruction address: 0xd00000000e682c90
cpu 0x1: Vector: 300 (Data Access) at [c000000fc75ffa20]
    pc: d00000000e682c90: .lpfc_io_error_detected+0x30/0x240 [lpfc]
    lr: d00000000e682c8c: .lpfc_io_error_detected+0x2c/0x240 [lpfc]
    sp: c000000fc75ffca0
   msr: 8000000000009032
   dar: 490
 dsisr: 40000000
  current = 0xc000000fc79b88b0
  paca    = 0xc00000000edb0380	 softe: 0	 irq_happened: 0x00
    pid   = 3386, comm = eehd
enter ? for help
[c000000fc75ffca0] c000000fc75ffd30 (unreliable)
[c000000fc75ffd30] c00000000004fd3c .eeh_report_error+0x7c/0xf0
[c000000fc75ffdc0] c00000000004ee00 .eeh_pe_dev_traverse+0xa0/0x180
[c000000fc75ffe70] c00000000004ffd8 .eeh_handle_event+0x68/0x300
[c000000fc75fff00] c0000000000503a0 .eeh_event_handler+0x130/0x1a0
[c000000fc75fff90] c000000000020138 .kernel_thread+0x54/0x70
1:mon>

The patch increases the reference of the corresponding driver modules
while EEH core does the negotiation with PCI device driver so that the
corresponding driver modules can't be unloaded during the period and
we're safe to refer the callbacks.

Reported-by: Alexey Kardashevskiy 
Signed-off-by: Gavin Shan 
Signed-off-by: Benjamin Herrenschmidt 
[ herton: backported for 3.5, adjusted driver assignments, return 0
  instead of NULL, assume dev is not NULL ]
Signed-off-by: Herton Ronaldo Krzesinski 
Cc: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

KVM: x86: invalid opcode oops on SET_SREGS with OSXSAVE bit set (CVE-2012-4461)

2012-12-03T19:47:11+00:00

commit 6d1068b3a98519247d8ba4ec85cd40ac136dbdf9 upstream.

On hosts without the XSAVE support unprivileged local user can trigger
oops similar to the one below by setting X86_CR4_OSXSAVE bit in guest
cr4 register using KVM_SET_SREGS ioctl and later issuing KVM_RUN
ioctl.

invalid opcode: 0000 [#2] SMP
Modules linked in: tun ip6table_filter ip6_tables ebtable_nat ebtables
...
Pid: 24935, comm: zoog_kvm_monito Tainted: G      D      3.2.0-3-686-pae
EIP: 0060:[] EFLAGS: 00210246 CPU: 0
EIP is at kvm_arch_vcpu_ioctl_run+0x92a/0xd13 [kvm]
EAX: 00000001 EBX: 000f387e ECX: 00000000 EDX: 00000000
ESI: 00000000 EDI: 00000000 EBP: ef5a0060 ESP: d7c63e70
 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
Process zoog_kvm_monito (pid: 24935, ti=d7c62000 task=ed84a0c0
task.ti=d7c62000)
Stack:
 00000001 f70a1200 f8b940a9 ef5a0060 00000000 00200202 f8769009 00000000
 ef5a0060 000f387e eda5c020 8722f9c8 00015bae 00000000 ed84a0c0 ed84a0c0
 c12bf02d 0000ae80 ef7f8740 fffffffb f359b740 ef5a0060 f8b85dc1 0000ae80
Call Trace:
 [] ? kvm_arch_vcpu_ioctl_set_sregs+0x2fe/0x308 [kvm]
...
 [] ? syscall_call+0x7/0xb
Code: 89 e8 e8 14 ee ff ff ba 00 00 04 00 89 e8 e8 98 48 ff ff 85 c0 74
1e 83 7d 48 00 75 18 8b 85 08 07 00 00 31 c9 8b 95 0c 07 00 00 <0f> 01
d1 c7 45 48 01 00 00 00 c7 45 1c 01 00 00 00 0f ae f0 89
EIP: [] kvm_arch_vcpu_ioctl_run+0x92a/0xd13 [kvm] SS:ESP
0068:d7c63e70

QEMU first retrieves the supported features via KVM_GET_SUPPORTED_CPUID
and then sets them later. So guest's X86_FEATURE_XSAVE should be masked
out on hosts without X86_FEATURE_XSAVE, making kvm_set_cr4 with
X86_CR4_OSXSAVE fail. Userspaces that allow specifying guest cpuid with
X86_FEATURE_XSAVE even on hosts that do not support it, might be
susceptible to this attack from inside the guest as well.

Allow setting X86_CR4_OSXSAVE bit only if host has XSAVE support.

Signed-off-by: Petr Matousek 
Signed-off-by: Marcelo Tosatti 
Signed-off-by: Greg Kroah-Hartman

sparc64: not any error from do_sigaltstack() should fail rt_sigreturn()

2012-12-03T19:47:10+00:00

commit fae2ae2a900a5c7bb385fe4075f343e7e2d5daa2 upstream.

If a signal handler is executed on altstack and another signal comes,
we will end up with rt_sigreturn() on return from the second handler
getting -EPERM from do_sigaltstack().  It's perfectly OK, since we
are not asking to change the settings; in fact, they couldn't have been
changed during the second handler execution exactly because we'd been
on altstack all along.  64bit sigreturn on sparc treats any error from
do_sigaltstack() as "SIGSEGV now"; we need to switch to the same semantics
we are using on other architectures.

Signed-off-by: Al Viro 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

PARISC: fix user-triggerable panic on parisc

2012-12-03T19:47:05+00:00

commit 441a179dafc0f99fc8b3a8268eef66958621082e upstream.

int sys32_rt_sigprocmask(int how, compat_sigset_t __user *set, compat_sigset_t __user *oset,
                                    unsigned int sigsetsize)
{
        sigset_t old_set, new_set;
        int ret;

        if (set && get_sigset32(set, &new_set, sigsetsize))

...
static int
get_sigset32(compat_sigset_t __user *up, sigset_t *set, size_t sz)
{
        compat_sigset_t s;
        int r;

        if (sz != sizeof *set) panic("put_sigset32()");

In other words, rt_sigprocmask(69, (void *)69, 69) done by 32bit process
will promptly panic the box.

Signed-off-by: Al Viro 
Signed-off-by: James Bottomley 
Signed-off-by: Greg Kroah-Hartman