linux-toradex.git/arch/x86, branch v3.19.3

x86/apic/numachip: Fix sibling map with NumaChip

2015-03-26T12:59:48+00:00

commit c8a470cab030bae8f9e6e5cfff72b047b7c627a7 upstream.

On NumaChip systems, the physical processor ID assignment wasn't
accounting for the number of nodes in AMD multi-module
processors, giving an incorrect sibling map:

  $ cd /sys/devices/system/cpu/cpu29/topology
  $ grep . *
  core_id:5
  core_siblings:00000000,ff000000
  core_siblings_list:24-31
  physical_package_id:3
  thread_siblings:00000000,30000000
  thread_siblings_list:28-29

This fixes it:

  $ cd /sys/devices/system/cpu/cpu29/topology
  $ grep . *
  core_id:5
  core_siblings:00000000,ffff0000
  core_siblings_list:16-31
  physical_package_id:1
  thread_siblings:00000000,30000000
  thread_siblings_list:28-29

Signed-off-by: Daniel J Blueman 
Signed-off-by: Borislav Petkov 
Cc: H. Peter Anvin 
Cc: Steffen Persvold 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/1426135950-10110-1-git-send-email-daniel@numascale.com
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

x86/asm/entry/32: Fix user_mode() misuses

2015-03-26T12:59:48+00:00

commit 394838c96013ba414a24ffe7a2a593a9154daadf upstream.

The one in do_debug() is probably harmless, but better safe than sorry.

Signed-off-by: Andy Lutomirski 
Cc: Borislav Petkov 
Cc: Dave Hansen 
Cc: H. Peter Anvin 
Cc: Linus Torvalds 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/d67deaa9df5458363623001f252d1aee3215d014.1425948056.git.luto@amacapital.net
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

x86/vdso: Fix the build on GCC5

2015-03-26T12:59:48+00:00

commit e893286918d2cde3a94850d8f7101cd1039e0c62 upstream.

On gcc5 the kernel does not link:

  ld: .eh_frame_hdr table[4] FDE at 0000000000000648 overlaps table[5] FDE at 0000000000000670.

Because prior GCC versions always emitted NOPs on ALIGN directives, but
gcc5 started omitting them.

.LSTARTFDEDLSI1 says:

        /* HACK: The dwarf2 unwind routines will subtract 1 from the
           return address to get an address in the middle of the
           presumed call instruction.  Since we didn't get here via
           a call, we need to include the nop before the real start
           to make up for it.  */
        .long .LSTART_sigreturn-1-.     /* PC-relative start address */

But commit 69d0627a7f6e ("x86 vDSO: reorder vdso32 code") from 2.6.25
replaced .org __kernel_vsyscall+32,0x90 by ALIGN right before
__kernel_sigreturn.

Of course, ALIGN need not generate any NOP in there. Esp. gcc5 collapses
vclock_gettime.o and int80.o together with no generated NOPs as "ALIGN".

So fix this by adding to that point at least a single NOP and make the
function ALIGN possibly with more NOPs then.

Kudos for reporting and diagnosing should go to Richard.

Reported-by: Richard Biener 
Signed-off-by: Jiri Slaby 
Acked-by: Andy Lutomirski 
Cc: Borislav Petkov 
Cc: H. Peter Anvin 
Cc: Linus Torvalds 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/1425543211-12542-1-git-send-email-jslaby@suse.cz
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

kvm: move advertising of KVM_CAP_IRQFD to common code

2015-03-26T12:59:48+00:00

commit dc9be0fac70a2ad86e31a81372bb0bdfb6945353 upstream.

POWER supports irqfds but forgot to advertise them.  Some userspace does
not check for the capability, but others check it---thus they work on
x86 and s390 but not POWER.

To avoid that other architectures in the future make the same mistake, let
common code handle KVM_CAP_IRQFD the same way as KVM_CAP_IRQFD_RESAMPLE.

Reported-and-tested-by: Greg Kurz 
Fixes: 297e21053a52f060944e9f0de4c64fad9bcd72fc
Signed-off-by: Paolo Bonzini 
Signed-off-by: Marcelo Tosatti 
Signed-off-by: Greg Kroah-Hartman

x86/fpu: Drop_fpu() should not assume that tsk equals current

2015-03-26T12:59:47+00:00

commit f4c3686386393c120710dd34df2a74183ab805fd upstream.

drop_fpu() does clear_used_math() and usually this is correct
because tsk == current.

However switch_fpu_finish()->restore_fpu_checking() is called before
__switch_to() updates the "current_task" variable. If it fails,
we will wrongly clear the PF_USED_MATH flag of the previous task.

So use clear_stopped_child_used_math() instead.

Signed-off-by: Oleg Nesterov 
Signed-off-by: Borislav Petkov 
Reviewed-by: Rik van Riel 
Cc: Andy Lutomirski 
Cc: Borislav Petkov 
Cc: Dave Hansen 
Cc: Fenghua Yu 
Cc: H. Peter Anvin 
Cc: Linus Torvalds 
Cc: Pekka Riikonen 
Cc: Quentin Casasnovas 
Cc: Suresh Siddha 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/20150309171041.GB11388@redhat.com
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

x86/fpu: Avoid math_state_restore() without used_math() in __restore_xstate_sig()

2015-03-26T12:59:47+00:00

commit a7c80ebcac3068b1c3cb27d538d29558c30010c8 upstream.

math_state_restore() assumes it is called with irqs disabled,
but this is not true if the caller is __restore_xstate_sig().

This means that if ia32_fxstate == T and __copy_from_user()
fails, __restore_xstate_sig() returns with irqs disabled too.

This triggers:

  BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:41
   dump_stack
   ___might_sleep
   ? _raw_spin_unlock_irqrestore
   __might_sleep
   down_read
   ? _raw_spin_unlock_irqrestore
   print_vma_addr
   signal_fault
   sys32_rt_sigreturn

Change __restore_xstate_sig() to call set_used_math()
unconditionally. This avoids enabling and disabling interrupts
in math_state_restore(). If copy_from_user() fails, we can
simply do fpu_finit() by hand.

[ Note: this is only the first step. math_state_restore() should
        not check used_math(), it should set this flag. While
	init_fpu() should simply die. ]

Signed-off-by: Oleg Nesterov 
Signed-off-by: Borislav Petkov 
Cc: Andy Lutomirski 
Cc: Borislav Petkov 
Cc: Dave Hansen 
Cc: Fenghua Yu 
Cc: H. Peter Anvin 
Cc: Linus Torvalds 
Cc: Pekka Riikonen 
Cc: Quentin Casasnovas 
Cc: Rik van Riel 
Cc: Suresh Siddha 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/20150307153844.GB25954@redhat.com
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

crypto: aesni - fix memory usage in GCM decryption

2015-03-26T12:59:47+00:00

commit ccfe8c3f7e52ae83155cb038753f4c75b774ca8a upstream.

The kernel crypto API logic requires the caller to provide the
length of (ciphertext || authentication tag) as cryptlen for the
AEAD decryption operation. Thus, the cipher implementation must
calculate the size of the plaintext output itself and cannot simply use
cryptlen.

The RFC4106 GCM decryption operation tries to overwrite cryptlen memory
in req->dst. As the destination buffer for decryption only needs to hold
the plaintext memory but cryptlen references the input buffer holding
(ciphertext || authentication tag), the assumption of the destination
buffer length in RFC4106 GCM operation leads to a too large size. This
patch simply uses the already calculated plaintext size.

In addition, this patch fixes the offset calculation of the AAD buffer
pointer: as mentioned before, cryptlen already includes the size of the
tag. Thus, the tag does not need to be added. With the addition, the AAD
will be written beyond the already allocated buffer.

Note, this fixes a kernel crash that can be triggered from user space
via AF_ALG(aead) -- simply use the libkcapi test application
from [1] and update it to use rfc4106-gcm-aes.

Using [1], the changes were tested using CAVS vectors to demonstrate
that the crypto operation still delivers the right results.

[1] http://www.chronox.de/libkcapi.html

CC: Tadeusz Struk 
Signed-off-by: Stephan Mueller 
Signed-off-by: Herbert Xu 
Signed-off-by: Greg Kroah-Hartman

x86/xen: correct bug in p2m list initialization

2015-03-26T12:59:46+00:00

commit b8f05c8803fce899d79ca66f8d7f348cf15fb40e upstream.

Commit 054954eb051f35e74b75a566a96fe756015352c8 ("xen: switch to
linear virtual mapped sparse p2m list") introduced an error.

During initialization of the p2m list a p2m identity area mapped by
a complete identity pmd entry has to be split up into smaller chunks
sometimes, if a non-identity pfn is introduced in this area.

If this non-identity pfn is not at index 0 of a p2m page the new
p2m page needed is initialized with wrong identity entries, as the
identity pfns don't start with the value corresponding to index 0,
but with the initial non-identity pfn. This results in weird wrong
mappings.

Correct the wrong initialization by starting with the correct pfn.

Reported-by: Stefan Bader 
Signed-off-by: Juergen Gross 
Tested-by: Stefan Bader 
Signed-off-by: David Vrabel 
Signed-off-by: Greg Kroah-Hartman

KVM: emulate: fix CMPXCHG8B on 32-bit hosts

2015-03-18T13:10:59+00:00

commit 4ff6f8e61eb7f96d3ca535c6d240f863ccd6fb7d upstream.

This has been broken for a long time: it broke first in 2.6.35, then was
almost fixed in 2.6.36 but this one-liner slipped through the cracks.
The bug shows up as an infinite loop in Windows 7 (and newer) boot on
32-bit hosts without EPT.

Windows uses CMPXCHG8B to write to page tables, which causes a
page fault if running without EPT; the emulator is then called from
kvm_mmu_page_fault.  The loop then happens if the higher 4 bytes are
not 0; the common case for this is that the NX bit (bit 63) is 1.

Fixes: 6550e1f165f384f3a46b60a1be9aba4bc3c2adad
Fixes: 16518d5ada690643453eb0aef3cc7841d3623c2d
Reported-by: Erik Rull 
Tested-by: Erik Rull 
Signed-off-by: Paolo Bonzini 
Signed-off-by: Greg Kroah-Hartman

x86/fpu/xsaves: Fix improper uses of __ex_table

2015-03-18T13:10:57+00:00

commit 06c8173eb92bbfc03a0fe8bb64315857d0badd06 upstream.

Commit:

  f31a9f7c7169 ("x86/xsaves: Use xsaves/xrstors to save and restore xsave area")

introduced alternative instructions for XSAVES/XRSTORS and commit:

  adb9d526e982 ("x86/xsaves: Add xsaves and xrstors support for booting time")

added support for the XSAVES/XRSTORS instructions at boot time.

Unfortunately both failed to properly protect them against faulting:

The 'xstate_fault' macro will use the closest label named '1'
backward and that ends up in the .altinstr_replacement section
rather than in .text. This means that the kernel will never find
in the __ex_table the .text address where this instruction might
fault, leading to serious problems if userspace manages to
trigger the fault.

Signed-off-by: Quentin Casasnovas 
Signed-off-by: Jamie Iles 
[ Improved the changelog, fixed some whitespace noise. ]
Acked-by: Borislav Petkov 
Acked-by: Linus Torvalds 
Cc: Allan Xavier 
Cc: H. Peter Anvin 
Cc: Thomas Gleixner 
Fixes: adb9d526e982 ("x86/xsaves: Add xsaves and xrstors support for booting time")
Fixes: f31a9f7c7169 ("x86/xsaves: Use xsaves/xrstors to save and restore xsave area")
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman