litmus-rt.git/arch/x86/include/asm, branch test The LITMUS^RT kernel. Add hrtimer_start_on() support 2015-08-09T10:21:17+00:00 Bjoern Brandenburg bbb@mpi-sws.org 2015-08-09T11:18:46+00:00 5014e7011964ff46b2d73cf91a05ed9eed5a8fa2 This patch adds hrtimer_start_on(), which allows arming timers on remote CPUs. This is needed to avoided timer interrupts on "shielded" CPUs and is also useful for implementing semi-partitioned schedulers. 
This patch adds hrtimer_start_on(), which allows arming timers on
remote CPUs.  This is needed to avoided timer interrupts on "shielded"
CPUs and is also useful for implementing semi-partitioned schedulers.
Feather-Trace: add x86 binary rewriting implementation 2015-08-09T10:21:16+00:00 Bjoern Brandenburg bbb@mpi-sws.org 2015-08-09T11:18:44+00:00 ee573d8bfbd6397051f46fd3e52f0aa45b30a887 This patch adds the x86-specific implementation of Feather-Trace triggers that works by rewriting jump instructions. 
This patch adds the x86-specific implementation of Feather-Trace
triggers that works by rewriting jump instructions.
KVM: x86: make vapics_in_nmi_mode atomic 2015-07-10T16:49:37+00:00 Radim Krčmář rkrcmar@redhat.com 2015-07-01T13:31:49+00:00 8ed8b759437fadfd18202be9bb65a7f80c3c6d63 commit 42720138b06301cc8a7ee8a495a6d021c4b6a9bc upstream. Writes were a bit racy, but hard to turn into a bug at the same time. (Particularly because modern Linux doesn't use this feature anymore.) Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> [Actually the next patch makes it much, much easier to trigger the race so I'm including this one for stable@ as well. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 42720138b06301cc8a7ee8a495a6d021c4b6a9bc upstream.

Writes were a bit racy, but hard to turn into a bug at the same time.
(Particularly because modern Linux doesn't use this feature anymore.)

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
[Actually the next patch makes it much, much easier to trigger the race
 so I'm including this one for stable@ as well. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86/asm/irq: Stop relying on magic JMP behavior for early_idt_handlers 2015-06-02T07:39:40+00:00 Andy Lutomirski luto@kernel.org 2015-05-22T23:15:47+00:00 425be5679fd292a3c36cb1fe423086708a99f11a The early_idt_handlers asm code generates an array of entry points spaced nine bytes apart. It's not really clear from that code or from the places that reference it what's going on, and the code only works in the first place because GAS never generates two-byte JMP instructions when jumping to global labels. Clean up the code to generate the correct array stride (member size) explicitly. This should be considerably more robust against screw-ups, as GAS will warn if a .fill directive has a negative count. Using '. =' to advance would have been even more robust (it would generate an actual error if it tried to move backwards), but it would pad with nulls, confusing anyone who tries to disassemble the code. The new scheme should be much clearer to future readers. While we're at it, improve the comments and rename the array and common code. Binutils may start relaxing jumps to non-weak labels. If so, this change will fix our build, and we may need to backport this change. Before, on x86_64: 0000000000000000 <early_idt_handlers>: 0: 6a 00 pushq $0x0 2: 6a 00 pushq $0x0 4: e9 00 00 00 00 jmpq 9 <early_idt_handlers+0x9> 5: R_X86_64_PC32 early_idt_handler-0x4 ... 48: 66 90 xchg %ax,%ax 4a: 6a 08 pushq $0x8 4c: e9 00 00 00 00 jmpq 51 <early_idt_handlers+0x51> 4d: R_X86_64_PC32 early_idt_handler-0x4 ... 117: 6a 00 pushq $0x0 119: 6a 1f pushq $0x1f 11b: e9 00 00 00 00 jmpq 120 <early_idt_handler> 11c: R_X86_64_PC32 early_idt_handler-0x4 After: 0000000000000000 <early_idt_handler_array>: 0: 6a 00 pushq $0x0 2: 6a 00 pushq $0x0 4: e9 14 01 00 00 jmpq 11d <early_idt_handler_common> ... 48: 6a 08 pushq $0x8 4a: e9 d1 00 00 00 jmpq 120 <early_idt_handler_common> 4f: cc int3 50: cc int3 ... 117: 6a 00 pushq $0x0 119: 6a 1f pushq $0x1f 11b: eb 03 jmp 120 <early_idt_handler_common> 11d: cc int3 11e: cc int3 11f: cc int3 Signed-off-by: Andy Lutomirski <luto@kernel.org> Acked-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Binutils <binutils@sourceware.org> Cc: Borislav Petkov <bp@alien8.de> Cc: H.J. Lu <hjl.tools@gmail.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/ac027962af343b0c599cbfcf50b945ad2ef3d7a8.1432336324.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> 
The early_idt_handlers asm code generates an array of entry
points spaced nine bytes apart.  It's not really clear from that
code or from the places that reference it what's going on, and
the code only works in the first place because GAS never
generates two-byte JMP instructions when jumping to global
labels.

Clean up the code to generate the correct array stride (member size)
explicitly. This should be considerably more robust against
screw-ups, as GAS will warn if a .fill directive has a negative
count.  Using '. =' to advance would have been even more robust
(it would generate an actual error if it tried to move
backwards), but it would pad with nulls, confusing anyone who
tries to disassemble the code.  The new scheme should be much
clearer to future readers.

While we're at it, improve the comments and rename the array and
common code.

Binutils may start relaxing jumps to non-weak labels.  If so,
this change will fix our build, and we may need to backport this
change.

Before, on x86_64:

  0000000000000000 <early_idt_handlers>:
     0:   6a 00                   pushq  $0x0
     2:   6a 00                   pushq  $0x0
     4:   e9 00 00 00 00          jmpq   9 <early_idt_handlers+0x9>
                          5: R_X86_64_PC32        early_idt_handler-0x4
  ...
    48:   66 90                   xchg   %ax,%ax
    4a:   6a 08                   pushq  $0x8
    4c:   e9 00 00 00 00          jmpq   51 <early_idt_handlers+0x51>
                          4d: R_X86_64_PC32       early_idt_handler-0x4
  ...
   117:   6a 00                   pushq  $0x0
   119:   6a 1f                   pushq  $0x1f
   11b:   e9 00 00 00 00          jmpq   120 <early_idt_handler>
                          11c: R_X86_64_PC32      early_idt_handler-0x4

After:

  0000000000000000 <early_idt_handler_array>:
     0:   6a 00                   pushq  $0x0
     2:   6a 00                   pushq  $0x0
     4:   e9 14 01 00 00          jmpq   11d <early_idt_handler_common>
  ...
    48:   6a 08                   pushq  $0x8
    4a:   e9 d1 00 00 00          jmpq   120 <early_idt_handler_common>
    4f:   cc                      int3
    50:   cc                      int3
  ...
   117:   6a 00                   pushq  $0x0
   119:   6a 1f                   pushq  $0x1f
   11b:   eb 03                   jmp    120 <early_idt_handler_common>
   11d:   cc                      int3
   11e:   cc                      int3
   11f:   cc                      int3

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Binutils <binutils@sourceware.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H.J. Lu <hjl.tools@gmail.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/ac027962af343b0c599cbfcf50b945ad2ef3d7a8.1432336324.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
x86/asm/entry/32: Really make user_mode() work correctly for VM86 mode 2015-05-29T07:46:40+00:00 Jan Beulich JBeulich@suse.com 2015-05-28T08:16:45+00:00 7ba554b5ac69e5f3edac9ce3233beb5acd480878 While commit efa7045103 ("x86/asm/entry: Make user_mode() work correctly if regs came from VM86 mode") claims that "user_mode() is now identical to user_mode_vm()", this wasn't actually the case - no prior commit made it so. Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/5566EB0D020000780007E655@mail.emea.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> 
While commit efa7045103 ("x86/asm/entry: Make user_mode() work
correctly if regs came from VM86 mode") claims that "user_mode()
is now identical to user_mode_vm()", this wasn't actually the
case - no prior commit made it so.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/5566EB0D020000780007E655@mail.emea.novell.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm 2015-05-22T03:15:16+00:00 Linus Torvalds torvalds@linux-foundation.org 2015-05-22T03:15:16+00:00 f0d8690ad443069b26df43a1be09c0f14a928eb9 Pull KVM fixes from Paolo Bonzini: "This includes a fix for two oopses, one on PPC and on x86. The rest is fixes for bugs with newer Intel processors" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: kvm/fpu: Enable eager restore kvm FPU for MPX Revert "KVM: x86: drop fpu_activate hook" kvm: fix crash in kvm_vcpu_reload_apic_access_page KVM: MMU: fix SMAP virtualization KVM: MMU: fix CR4.SMEP=1, CR0.WP=0 with shadow pages KVM: MMU: fix smap permission check KVM: PPC: Book3S HV: Fix list traversal in error case 
Pull KVM fixes from Paolo Bonzini:
 "This includes a fix for two oopses, one on PPC and on x86.

  The rest is fixes for bugs with newer Intel processors"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  kvm/fpu: Enable eager restore kvm FPU for MPX
  Revert "KVM: x86: drop fpu_activate hook"
  kvm: fix crash in kvm_vcpu_reload_apic_access_page
  KVM: MMU: fix SMAP virtualization
  KVM: MMU: fix CR4.SMEP=1, CR0.WP=0 with shadow pages
  KVM: MMU: fix smap permission check
  KVM: PPC: Book3S HV: Fix list traversal in error case
kvm/fpu: Enable eager restore kvm FPU for MPX 2015-05-20T10:30:26+00:00 Liang Li liang.z.li@intel.com 2015-05-20T20:41:25+00:00 c447e76b4cabb49ddae8e49c5758f031f35d55fb The MPX feature requires eager KVM FPU restore support. We have verified that MPX cannot work correctly with the current lazy KVM FPU restore mechanism. Eager KVM FPU restore should be enabled if the MPX feature is exposed to VM. Signed-off-by: Yang Zhang <yang.z.zhang@intel.com> Signed-off-by: Liang Li <liang.z.li@intel.com> [Also activate the FPU on AMD processors. - Paolo] Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> 
The MPX feature requires eager KVM FPU restore support. We have verified
that MPX cannot work correctly with the current lazy KVM FPU restore
mechanism. Eager KVM FPU restore should be enabled if the MPX feature is
exposed to VM.

Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Signed-off-by: Liang Li <liang.z.li@intel.com>
[Also activate the FPU on AMD processors. - Paolo]
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Revert "KVM: x86: drop fpu_activate hook" 2015-05-20T10:30:15+00:00 Paolo Bonzini pbonzini@redhat.com 2015-05-20T09:33:43+00:00 0fdd74f7784b5cdff7075736992bbb149b1ae49c This reverts commit 4473b570a7ebb502f63f292ccfba7df622e5fdd3. We'll use the hook again. Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> 
This reverts commit 4473b570a7ebb502f63f292ccfba7df622e5fdd3.  We'll
use the hook again.

Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: MMU: fix SMAP virtualization 2015-05-11T15:17:50+00:00 Xiao Guangrong guangrong.xiao@linux.intel.com 2015-05-11T14:55:21+00:00 0be0226f07d14b153a5eedf2bb86e1eb7dcefab5 KVM may turn a user page to a kernel page when kernel writes a readonly user page if CR0.WP = 1. This shadow page entry will be reused after SMAP is enabled so that kernel is allowed to access this user page Fix it by setting SMAP && !CR0.WP into shadow page's role and reset mmu once CR4.SMAP is updated Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> 
KVM may turn a user page to a kernel page when kernel writes a readonly
user page if CR0.WP = 1. This shadow page entry will be reused after
SMAP is enabled so that kernel is allowed to access this user page

Fix it by setting SMAP && !CR0.WP into shadow page's role and reset mmu
once CR4.SMAP is updated

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Merge tag 'for-linus-4.1b-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip 2015-05-06T22:58:06+00:00 Linus Torvalds torvalds@linux-foundation.org 2015-05-06T22:58:06+00:00 0e1dc4274828f64fcb56fc7b950acdc5ff7a395f Pull xen bug fixes from David Vrabel: - fix blkback regression if using persistent grants - fix various event channel related suspend/resume bugs - fix AMD x86 regression with X86_BUG_SYSRET_SS_ATTRS - SWIOTLB on ARM now uses frames <4 GiB (if available) so device only capable of 32-bit DMA work. * tag 'for-linus-4.1b-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: Add __GFP_DMA flag when xen_swiotlb_init gets free pages on ARM hypervisor/x86/xen: Unset X86_BUG_SYSRET_SS_ATTRS on Xen PV guests xen/events: Set irq_info->evtchn before binding the channel to CPU in __startup_pirq() xen/console: Update console event channel on resume xen/xenbus: Update xenbus event channel on resume xen/events: Clear cpu_evtchn_mask before resuming xen-pciback: Add name prefix to global 'permissive' variable xen: Suspend ticks on all CPUs during suspend xen/grant: introduce func gnttab_unmap_refs_sync() xen/blkback: safely unmap purge persistent grants 
Pull xen bug fixes from David Vrabel:

 - fix blkback regression if using persistent grants

 - fix various event channel related suspend/resume bugs

 - fix AMD x86 regression with X86_BUG_SYSRET_SS_ATTRS

 - SWIOTLB on ARM now uses frames <4 GiB (if available) so device only
   capable of 32-bit DMA work.

* tag 'for-linus-4.1b-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: Add __GFP_DMA flag when xen_swiotlb_init gets free pages on ARM
  hypervisor/x86/xen: Unset X86_BUG_SYSRET_SS_ATTRS on Xen PV guests
  xen/events: Set irq_info->evtchn before binding the channel to CPU in __startup_pirq()
  xen/console: Update console event channel on resume
  xen/xenbus: Update xenbus event channel on resume
  xen/events: Clear cpu_evtchn_mask before resuming
  xen-pciback: Add name prefix to global 'permissive' variable
  xen: Suspend ticks on all CPUs during suspend
  xen/grant: introduce func gnttab_unmap_refs_sync()
  xen/blkback: safely unmap purge persistent grants