Commit Graph

15804 Commits

Author SHA1 Message Date
H. Peter Anvin
63bcff2a30 x86, smap: Add STAC and CLAC instructions to control user space access
When Supervisor Mode Access Prevention (SMAP) is enabled, access to
userspace from the kernel is controlled by the AC flag.  To make the
performance of manipulating that flag acceptable, there are two new
instructions, STAC and CLAC, to set and clear it.

This patch adds those instructions, via alternative(), when the SMAP
feature is enabled.  It also adds X86_EFLAGS_AC unconditionally to the
SYSCALL entry mask; there is simply no reason to make that one
conditional.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1348256595-29119-9-git-send-email-hpa@linux.intel.com
2012-09-21 12:45:27 -07:00
H. Peter Anvin
a052858fab x86, uaccess: Merge prototypes for clear_user/__clear_user
The prototypes for clear_user() and __clear_user() are identical in
the 32- and 64-bit headers.  No functionality change.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1348256595-29119-8-git-send-email-hpa@linux.intel.com
2012-09-21 12:45:26 -07:00
H. Peter Anvin
51ae4a2d77 x86, smap: Add a header file with macros for STAC/CLAC
The STAC/CLAC instructions are only available with SMAP, but on the
other hand they aren't needed if SMAP is not available, or before we
start to run userspace, so construct them as alternatives which start
out as noops and are enabled by the alternatives mechanism.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1348256595-29119-7-git-send-email-hpa@linux.intel.com
2012-09-21 12:45:26 -07:00
H. Peter Anvin
76f30759f6 x86, alternative: Add header guards to <asm/alternative-asm.h>
Add header guards to protect <asm/alternative-asm.h> against multiple
inclusion.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1348256595-29119-6-git-send-email-hpa@linux.intel.com
2012-09-21 12:45:26 -07:00
H. Peter Anvin
9cebed423c x86, alternative: Use .pushsection/.popsection
.section/.previous doesn't nest.  Use .pushsection/.popsection in
<asm/alternative.h> so that they can be properly nested.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1348256595-29119-5-git-send-email-hpa@linux.intel.com
2012-09-21 12:45:25 -07:00
H. Peter Anvin
85fdf05cc3 x86, smap: Add CR4 bit for SMAP
Add X86_CR4_SMAP to <asm/processor-flags.h>.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1348256595-29119-4-git-send-email-hpa@linux.intel.com
2012-09-21 12:45:25 -07:00
H. Peter Anvin
8bd753be7a x86-32, mm: The WP test should be done on a kernel page
PAGE_READONLY includes user permission, but this is a page used
exclusively by the kernel; use PAGE_KERNEL_RO instead.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1348256595-29119-3-git-send-email-hpa@linux.intel.com
2012-09-21 12:45:25 -07:00
H. Peter Anvin
05194cfc54 x86, cpufeature: Add feature bit for SMAP
Add CPUID feature bit for Supervisor Mode Access Prevention (SMAP).

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/n/tip-ethzcr5nipikl6hd5q8ssepq@git.kernel.org
2012-09-09 11:12:04 -07:00
Michael S. Tsirkin
1d92128fe9 KVM: x86: fix KVM_GET_MSR for PV EOI
KVM_GET_MSR was missing support for PV EOI,
which is needed for migration.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-08-27 18:03:05 -03:00
Linus Torvalds
267560874c Three bug-fixes:
- Revert the kexec fix which caused on non-kexec shutdowns a race.
  - Reuse existing P2M leafs - instead of requiring to allocate a large
    area of bootup virtual address estate.
  - Fix a one-off error when adding PFNs for balloon pages.
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Merge tag 'stable/for-linus-3.6-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull three xen bug-fixes from Konrad Rzeszutek Wilk:
 - Revert the kexec fix which caused on non-kexec shutdowns a race.
 - Reuse existing P2M leafs - instead of requiring to allocate a large
   area of bootup virtual address estate.
 - Fix a one-off error when adding PFNs for balloon pages.

* tag 'stable/for-linus-3.6-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/setup: Fix one-off error when adding for-balloon PFNs to the P2M.
  xen/p2m: Reuse existing P2M leafs if they are filled with 1:1 PFNs or INVALID.
  Revert "xen PVonHVM: move shared_info to MMIO before kexec"
2012-08-25 17:31:59 -07:00
Linus Torvalds
6ec9776c28 Merge git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Marcelo Tosatti.

* git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86 emulator: use stack size attribute to mask rsp in stack ops
  KVM: MMU: Fix mmu_shrink() so that it can free mmu pages as intended
  ppc: e500_tlb memset clears nothing
  KVM: PPC: Add cache flush on page map
  KVM: PPC: Book3S HV: Fix incorrect branch in H_CEDE code
  KVM: x86: update KVM_SAVE_MSRS_BEGIN to correct value
2012-08-25 17:27:17 -07:00
Konrad Rzeszutek Wilk
c96aae1f7f xen/setup: Fix one-off error when adding for-balloon PFNs to the P2M.
When we are finished with return PFNs to the hypervisor, then
populate it back, and also mark the E820 MMIO and E820 gaps
as IDENTITY_FRAMEs, we then call P2M to set areas that can
be used for ballooning. We were off by one, and ended up
over-writting a P2M entry that most likely was an IDENTITY_FRAME.
For example:

1-1 mapping on 40000->40200
1-1 mapping on bc558->bc5ac
1-1 mapping on bc5b4->bc8c5
1-1 mapping on bc8c6->bcb7c
1-1 mapping on bcd00->100000
Released 614 pages of unused memory
Set 277889 page(s) to 1-1 mapping
Populating 40200-40466 pfn range: 614 pages added

=> here we set from 40466 up to bc559 P2M tree to be
INVALID_P2M_ENTRY. We should have done it up to bc558.

The end result is that if anybody is trying to construct
a PTE for PFN bc558 they end up with ~PAGE_PRESENT.

CC: stable@vger.kernel.org
Reported-by-and-Tested-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 10:14:52 -04:00
Andreas Herrmann
36bf50d769 x86, microcode, AMD: Fix broken ucode patch size check
This issue was recently observed on an AMD C-50 CPU where a patch of
maximum size was applied.

Commit be62adb492 ("x86, microcode, AMD: Simplify ucode verification")
added current_size in get_matching_microcode(). This is calculated as
size of the ucode patch + 8 (ie. size of the header). Later this is
compared against the maximum possible ucode patch size for a CPU family.
And of course this fails if the patch has already maximum size.

Cc: <stable@vger.kernel.org> [3.3+]
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Link: http://lkml.kernel.org/r/1344361461-10076-1-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-08-22 16:10:41 -07:00
Avi Kivity
5ad105e569 KVM: x86 emulator: use stack size attribute to mask rsp in stack ops
The sub-register used to access the stack (sp, esp, or rsp) is not
determined by the address size attribute like other memory references,
but by the stack segment's B bit (if not in x86_64 mode).

Fix by using the existing stack_mask() to figure out the correct mask.

This long-existing bug was exposed by a combination of a27685c33a
(emulate invalid guest state by default), which causes many more
instructions to be emulated, and a seabios change (possibly a bug) which
causes the high 16 bits of esp to become polluted across calls to real
mode software interrupts.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-08-22 18:54:26 -03:00
Takuya Yoshikawa
35f2d16bb9 KVM: MMU: Fix mmu_shrink() so that it can free mmu pages as intended
Although the possible race described in

  commit 85b7059169
  KVM: MMU: fix shrinking page from the empty mmu

was correct, the real cause of that issue was a more trivial bug of
mmu_shrink() introduced by

  commit 1952639665
  KVM: MMU: do not iterate over all VMs in mmu_shrink()

Here is the bug:

	if (kvm->arch.n_used_mmu_pages > 0) {
		if (!nr_to_scan--)
			break;
		continue;
	}

We skip VMs whose n_used_mmu_pages is not zero and try to shrink others:
in other words we try to shrink empty ones by mistake.

This patch reverses the logic so that mmu_shrink() can free pages from
the first VM whose n_used_mmu_pages is not zero.  Note that we also add
comments explaining the role of nr_to_scan which is not practically
important now, hoping this will be improved in the future.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-08-22 15:27:13 +03:00
Avi Kivity
cb09cad44f x86/alternatives: Fix p6 nops on non-modular kernels
Probably a leftover from the early days of self-patching, p6nops
are marked __initconst_or_module, which causes them to be
discarded in a non-modular kernel.  If something later triggers
patching, it will overwrite kernel code with garbage.

Reported-by: Tomas Racek <tracek@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Cc: Michael Tokarev <mjt@tls.msk.ru>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: qemu-devel@nongnu.org
Cc: Anthony Liguori <anthony@codemonkey.ws>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Alan Cox <alan@linux.intel.com>
Link: http://lkml.kernel.org/r/5034AE84.90708@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-22 12:09:49 +02:00
Liu, Chuansheng
2530cd4f44 x86/fixup_irq: Use cpu_online_mask instead of cpu_all_mask
When one CPU is going down and this CPU is the last one in irq
affinity, current code is setting cpu_all_mask as the new
affinity for that irq.

But for some systems (such as in Medfield Android mobile) the
firmware sends the interrupt to each CPU in the irq affinity
mask, averaged, and cpu_all_mask includes all potential CPUs,
i.e. offline ones as well.

So replace cpu_all_mask with cpu_online_mask.

Signed-off-by: liu chuansheng <chuansheng.liu@intel.com>
Acked-by: Yanmin Zhang <yanmin_zhang@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/27240C0AC20F114CBF8149A2696CBE4A137286@SHSMSX101.ccr.corp.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-22 10:36:08 +02:00
Richard Weinberger
83be4ffa1a x86/spinlocks: Fix comment in spinlock.h
This comment is no longer true.  We support up to 2^16 CPUs
because __ticket_t is an u16 if NR_CPUS is larger than 256.

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-22 09:52:47 +02:00
Michal Hocko
eb48c07146 mm: hugetlbfs: correctly populate shared pmd
Each page mapped in a process's address space must be correctly
accounted for in _mapcount.  Normally the rules for this are
straightforward but hugetlbfs page table sharing is different.  The page
table pages at the PMD level are reference counted while the mapcount
remains the same.

If this accounting is wrong, it causes bugs like this one reported by
Larry Woodman:

  kernel BUG at mm/filemap.c:135!
  invalid opcode: 0000 [#1] SMP
  CPU 22
  Modules linked in: bridge stp llc sunrpc binfmt_misc dcdbas microcode pcspkr acpi_pad acpi]
  Pid: 18001, comm: mpitest Tainted: G        W    3.3.0+ #4 Dell Inc. PowerEdge R620/07NDJ2
  RIP: 0010:[<ffffffff8112cfed>]  [<ffffffff8112cfed>] __delete_from_page_cache+0x15d/0x170
  Process mpitest (pid: 18001, threadinfo ffff880428972000, task ffff880428b5cc20)
  Call Trace:
    delete_from_page_cache+0x40/0x80
    truncate_hugepages+0x115/0x1f0
    hugetlbfs_evict_inode+0x18/0x30
    evict+0x9f/0x1b0
    iput_final+0xe3/0x1e0
    iput+0x3e/0x50
    d_kill+0xf8/0x110
    dput+0xe2/0x1b0
    __fput+0x162/0x240

During fork(), copy_hugetlb_page_range() detects if huge_pte_alloc()
shared page tables with the check dst_pte == src_pte.  The logic is if
the PMD page is the same, they must be shared.  This assumes that the
sharing is between the parent and child.  However, if the sharing is
with a different process entirely then this check fails as in this
diagram:

  parent
    |
    ------------>pmd
                 src_pte----------> data page
                                        ^
  other--------->pmd--------------------|
                  ^
  child-----------|
                 dst_pte

For this situation to occur, it must be possible for Parent and Other to
have faulted and failed to share page tables with each other.  This is
possible due to the following style of race.

  PROC A                                          PROC B
  copy_hugetlb_page_range                         copy_hugetlb_page_range
    src_pte == huge_pte_offset                      src_pte == huge_pte_offset
    !src_pte so no sharing                          !src_pte so no sharing

  (time passes)

  hugetlb_fault                                   hugetlb_fault
    huge_pte_alloc                                  huge_pte_alloc
      huge_pmd_share                                 huge_pmd_share
        LOCK(i_mmap_mutex)
        find nothing, no sharing
        UNLOCK(i_mmap_mutex)
                                                      LOCK(i_mmap_mutex)
                                                      find nothing, no sharing
                                                      UNLOCK(i_mmap_mutex)
      pmd_alloc                                       pmd_alloc
      LOCK(instantiation_mutex)
      fault
      UNLOCK(instantiation_mutex)
                                                  LOCK(instantiation_mutex)
                                                  fault
                                                  UNLOCK(instantiation_mutex)

These two processes are not poing to the same data page but are not
sharing page tables because the opportunity was missed.  When either
process later forks, the src_pte == dst pte is potentially insufficient.
As the check falls through, the wrong PTE information is copied in
(harmless but wrong) and the mapcount is bumped for a page mapped by a
shared page table leading to the BUG_ON.

This patch addresses the issue by moving pmd_alloc into huge_pmd_share
which guarantees that the shared pud is populated in the same critical
section as pmd.  This also means that huge_pte_offset test in
huge_pmd_share is serialized correctly now which in turn means that the
success of the sharing will be higher as the racing tasks see the pud
and pmd populated together.

Race identified and changelog written mostly by Mel Gorman.

{akpm@linux-foundation.org: attempt to make the huge_pmd_share() comment comprehensible, clean up coding style]
Reported-by: Larry Woodman <lwoodman@redhat.com>
Tested-by: Larry Woodman <lwoodman@redhat.com>
Reviewed-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Ken Chen <kenchen@google.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21 16:45:02 -07:00
Linus Torvalds
c71a35520f Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar.

A x32 socket ABI fix with a -stable backport tag among other fixes.

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x32: Use compat shims for {g,s}etsockopt
  Revert "x86-64/efi: Use EFI to deal with platform wall clock"
  x86, apic: fix broken legacy interrupts in the logical apic mode
  x86, build: Globally set -fno-pic
  x86, avx: don't use avx instructions with "noxsave" boot param
2012-08-20 10:36:18 -07:00
Linus Torvalds
f78602ab7c Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 perf fixes from Ingo Molnar.

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86: disable PEBS on a guest entry.
  perf/x86: Add Intel Westmere-EX uncore support
  perf/x86: Fixes for Nehalem-EX uncore driver
  perf, x86: Fix uncore_types_exit section mismatch
2012-08-20 10:34:21 -07:00
Mike Frysinger
515c7af85e x32: Use compat shims for {g,s}etsockopt
Some of the arguments to {g,s}etsockopt are passed in userland pointers.
If we try to use the 64bit entry point, we end up sometimes failing.

For example, dhcpcd doesn't run in x32:
	# dhcpcd eth0
	dhcpcd[1979]: version 5.5.6 starting
	dhcpcd[1979]: eth0: broadcasting for a lease
	dhcpcd[1979]: eth0: open_socket: Invalid argument
	dhcpcd[1979]: eth0: send_raw_packet: Bad file descriptor

The code in particular is getting back EINVAL when doing:
	struct sock_fprog pf;
	setsockopt(s, SOL_SOCKET, SO_ATTACH_FILTER, &pf, sizeof(pf));

Diving into the kernel code, we can see:
include/linux/filter.h:
	struct sock_fprog {
		unsigned short len;
		struct sock_filter __user *filter;
	};

net/core/sock.c:
	case SO_ATTACH_FILTER:
		ret = -EINVAL;
		if (optlen == sizeof(struct sock_fprog)) {
			struct sock_fprog fprog;

			ret = -EFAULT;
			if (copy_from_user(&fprog, optval, sizeof(fprog)))
				break;

			ret = sk_attach_filter(&fprog, sk);
		}
		break;

arch/x86/syscalls/syscall_64.tbl:
	54 common setsockopt sys_setsockopt
	55 common getsockopt sys_getsockopt

So for x64, sizeof(sock_fprog) is 16 bytes.  For x86/x32, it's 8 bytes.
This comes down to the pointer being 32bit for x32, which means we need
to do structure size translation.  But since x32 comes in directly to
sys_setsockopt, it doesn't get translated like x86.

After changing the syscall table and rebuilding glibc with the new kernel
headers, dhcp runs fine in an x32 userland.

Oddly, it seems like Linus noted the same thing during the initial port,
but I guess that was missed/lost along the way:
	https://lkml.org/lkml/2011/8/26/452

[ hpa: tagging for -stable since this is an ABI fix. ]

Bugzilla: https://bugs.gentoo.org/423649
Reported-by: Mads <mads@ab3.no>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Link: http://lkml.kernel.org/r/1345320697-15713-1-git-send-email-vapier@gentoo.org
Cc: H. J. Lu <hjl.tools@gmail.com>
Cc: <stable@vger.kernel.org> v3.4..v3.5
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-08-18 14:15:39 -07:00
Konrad Rzeszutek Wilk
250a41e0ec xen/p2m: Reuse existing P2M leafs if they are filled with 1:1 PFNs or INVALID.
If P2M leaf is completly packed with INVALID_P2M_ENTRY or with
1:1 PFNs (so IDENTITY_FRAME type PFNs), we can swap the P2M leaf
with either a p2m_missing or p2m_identity respectively. The old
page (which was created via extend_brk or was grafted on from the
mfn_list) can be re-used for setting new PFNs.

This also means we can remove git commit:
5bc6f9888d
xen/p2m: Reserve 8MB of _brk space for P2M leafs when populating back
which tried to fix this.

and make the amount that is required to be reserved much smaller.

CC: stable@vger.kernel.org # for 3.5 only.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-17 09:29:15 -04:00
Linus Torvalds
ad54e46113 Fix:
* On machines with large MMIO/PCI E820 spaces we fail to boot b/c
    we failed to pre-allocate large enough virtual space for extend_brk.
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Merge tag 'stable/for-linus-3.6-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull Xen fix from Konrad Rzeszutek Wilk:
 "Way back in v3.5 we added a mechanism to populate back pages that were
  released (they overlapped with MMIO regions), but neglected to reserve
  the proper amount of virtual space for extend_brk to work properly.

  Coincidentally some other commit aligned the _brk space to larger area
  so I didn't trigger this until it was run on a machine with more than
  2GB of MMIO space."

 * On machines with large MMIO/PCI E820 spaces we fail to boot b/c
   we failed to pre-allocate large enough virtual space for extend_brk.

* tag 'stable/for-linus-3.6-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/p2m: Reserve 8MB of _brk space for P2M leafs when populating back.
2012-08-16 11:31:59 -07:00
Konrad Rzeszutek Wilk
ca08649eb5 Revert "xen PVonHVM: move shared_info to MMIO before kexec"
This reverts commit 00e37bdb01.

During shutdown of PVHVM guests with more than 2VCPUs on certain
machines we can hit the race where the replaced shared_info is not
replaced fast enough and the PV time clock retries reading the same
area over and over without any any success and is stuck in an
infinite loop.

Acked-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-16 13:05:25 -04:00
H. Peter Anvin
f026cfa82f Revert "x86-64/efi: Use EFI to deal with platform wall clock"
This reverts commit bacef661ac.

This commit has been found to cause serious regressions on a number of
ASUS machines at the least.  We probably need to provide a 1:1 map in
addition to the EFI virtual memory map in order for this to work.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Reported-and-bisected-by: Jérôme Carretero <cJ-ko@zougloub.eu>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120805172903.5f8bb24c@zougloub.eu
2012-08-14 09:58:25 -07:00
Suresh Siddha
f1c6300183 x86, apic: fix broken legacy interrupts in the logical apic mode
Recent commit 332afa656e cleaned up
a workaround that updates irq_cfg domain for legacy irq's that
are handled by the IO-APIC. This was assuming that the recent
changes in assign_irq_vector() were sufficient to remove the workaround.

But this broke couple of AMD platforms. One of them seems to be
sending interrupts to the offline cpu's, resulting in spurious
"No irq handler for vector xx (irq -1)" messages when those cpu's come online.
And the other platform seems to always send the interrupt to the last logical
CPU (cpu-7). Recent changes had an unintended side effect of using only logical
cpu-0 in the IO-APIC RTE (during boot for the legacy interrupts) and this
broke the legacy interrupts not getting routed to the cpu-7 on the AMD
platform, resulting in a boot hang.

For now, reintroduce the removed workaround, (essentially not allowing the
vector to change for legacy irq's when io-apic starts to handle the irq. Which
also addressed the uninteded sife effect of just specifying cpu-0 in the
IO-APIC RTE for those irq's during boot).

Reported-and-tested-by: Robert Richter <robert.richter@amd.com>
Reported-and-tested-by: Borislav Petkov <bp@amd64.org>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1344453412.29170.5.camel@sbsiddha-desk.sc.intel.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-08-14 09:52:20 -07:00
Gleb Natapov
26a4f3c08d perf/x86: disable PEBS on a guest entry.
If PMU counter has PEBS enabled it is not enough to disable counter
on a guest entry since PEBS memory write can overshoot guest entry
and corrupt guest memory. Disabling PEBS during guest entry solves
the problem.

Tested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120809085234.GI3341@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-13 19:01:04 +02:00
Yan, Zheng
cb37af7712 perf/x86: Add Intel Westmere-EX uncore support
The Westmere-EX uncore is similar to the Nehalem-EX uncore. The
differences are:
 - Westmere-EX uncore has 10 instances of Cbox. The MSRs for Cbox8
   and Cbox9 in the Westmere-EX aren't contiguous with Cbox 0~7.
 - The fvid field in the ZDP_CTL_FVC register in the Mbox is
   different. It's 5 bits in the Nehalem-EX, 6 bits in the
   Westmere-EX.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1344229882-3907-3-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-13 19:01:04 +02:00
Yan, Zheng
ebb6cc0359 perf/x86: Fixes for Nehalem-EX uncore driver
This patch includes following fixes and update:
 - Only some events in the Sbox and Mbox can use the match/mask
   registers, add code to check this.
 - The format definitions for xbr_mm_cfg and xbr_match registers
   in the Rbox are wrong, xbr_mm_cfg should use 32 bits, xbr_match
   should use 64 bits.
 - Cleanup the Rbox code. Compute the addresses extra registers in
   the enable_event function instead of the hw_config function.
   This simplifies the code in nhmex_rbox_alter_er().

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1344229882-3907-2-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-13 19:01:03 +02:00
Borislav Petkov
cffa59baa5 perf, x86: Fix uncore_types_exit section mismatch
Fix the following section mismatch:

WARNING: arch/x86/kernel/cpu/built-in.o(.text+0x7ad9): Section mismatch in reference from the function uncore_types_exit() to the function .init.text:uncore_type_exit()

The function uncore_types_exit() references the function __init
uncore_type_exit().  This is often because uncore_types_exit lacks a
__init annotation or the annotation of uncore_type_exit is wrong.

caused by 14371cce03 ("perf: Add generic PCI uncore PMU device
support").

Cc: Zheng Yan <zheng.z.yan@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1339741902-8449-8-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-13 19:01:03 +02:00
Andrew Boie
484d90eec8 x86, build: Globally set -fno-pic
GCC built with nonstandard options can enable -fpic by default.
We never want this for 32-bit kernels and it will break the build.

[ hpa: Notably the Android toolchain apparently does this. ]

Change-Id: Iaab7d66e598b1c65ac4a4f0229eca2cd3d0d2898
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Link: http://lkml.kernel.org/r/1344624546-29691-1-git-send-email-andrew.p.boie@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-08-10 16:12:30 -07:00
Suresh Siddha
c6fd893da9 x86, avx: don't use avx instructions with "noxsave" boot param
Clear AVX, AVX2 features along with clearing XSAVE feature bits,
as part of the parsing "noxsave" parameter.

Fixes the kernel boot panic with "noxsave" boot parameter.

We could have checked cpu_has_osxsave along with cpu_has_avx etc, but Peter
mentioned clearing the feature bits will be better for uses like
static_cpu_has() etc.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1343755754.2041.2.camel@sbsiddha-desk.sc.intel.com
Cc: <stable@vger.kernel.org>	# v3.5
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-08-08 13:41:42 -07:00
Gleb Natapov
439793d4b3 KVM: x86: update KVM_SAVE_MSRS_BEGIN to correct value
When MSR_KVM_PV_EOI_EN was added to msrs_to_save array
KVM_SAVE_MSRS_BEGIN was not updated accordingly.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-08-05 16:52:38 +03:00
Linus Torvalds
d8579fd834 Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux
Pull ACPI and power management fixes from Len Brown:
 "A 3.3 sleep regression fixed, numa bugfix, plus some minor cleanups"

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
  ACPI processor: Fix tick_broadcast_mask online/offline regression
  ACPI: Only count valid srat memory structures
  ACPI: Untangle a return statement for better readability
  ACPI / PCI: Do not try to acquire _OSC control if that is hopeless
  ACPI: delete _GTS/_BFS support
  ACPI/x86: revert 'x86, acpi: Call acpi_enter_sleep_state via an asmlinkage C function from assembler'
  ACPI: replace strlen("string") with sizeof("string") -1
  ACPI / PM: Fix build warning in sleep.c for CONFIG_ACPI_SLEEP unset
2012-08-03 14:10:00 -07:00
Linus Torvalds
d79095eee2 Merge git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM bug fixes from Marcelo Tosatti:
 - Fix DS/ES segment register corruption on x86_32.
 - Fix kvmclock wallclock migration offset.
 - Fix PIT interrupt ACK vs system reset logic bug.

* git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: VMX: Fix ds/es corruption on i386 with preemption
  KVM: x86: apply kvmclock offset to guest wall clock time
  KVM: PIC: call ack notifiers for irqs that are dropped form irr
2012-08-03 11:21:29 -07:00
Linus Torvalds
1ca0049f2c Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Various fixes"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86-64, kcmp: The kcmp system call can be common
  arch/x86/kernel/kdebugfs.c: Ensure a consistent return value in error case
  x86/mce: Add quirk for instruction recovery on Sandy Bridge processors
  x86/mce: Move MCACOD defines from mce-severity.c to <asm/mce.h>
  x86/ioapic: Fix NULL pointer dereference on CPU hotplug after disabling irqs
  x86, nops: Missing break resulting in incorrect selection on Intel
  x86: CONFIG_CC_STACKPROTECTOR=y is no longer experimental
2012-08-03 10:59:36 -07:00
Linus Torvalds
bd463a0606 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Fix merge window fallout and fix sleep profiling (this was always
  broken, so it's not a fix for the merge window - we can skip this one
  from the head of the tree)."

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/trace: Add ability to set a target task for events
  perf/x86: Fix USER/KERNEL tagging of samples properly
  perf/x86/intel/uncore: Make UNCORE_PMU_HRTIMER_INTERVAL 64-bit
2012-08-03 10:57:20 -07:00
Len Brown
9d0b01a1bb Merge branches 'delete-gts-bfs', 'misc', 'novell-bugzilla-757888-numa' and 'osc-pcie' into base 2012-08-03 00:31:23 -04:00
Thomas Renninger
095adbb644 ACPI: Only count valid srat memory structures
Otherwise you could run into:
WARN_ON in numa_register_memblks(), because node_possible_map is zero

References: https://bugzilla.novell.com/show_bug.cgi?id=757888

On this machine (ProLiant ML570 G3) the SRAT table contains:
  - No processor affinities
  - One memory affinity structure (which is set disabled)

CC: Per Jessen <per@opensuse.org>
CC: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
2012-08-03 00:15:53 -04:00
Linus Torvalds
fc6bdb59a5 Merge branch 'for-linus-3.6' of git://dev.laptop.org/users/dilinger/linux-olpc
Pull OLPC platform updates from Andres Salomon:
 "These move the OLPC Embedded Controller driver out of
  arch/x86/platform and into drivers/platform/olpc.

  OLPC machines are now ARM-based (which means lots of x86 and ARM
  changes), but are typically pretty self-contained..  so it makes more
  sense to go through a separate OLPC tree after getting the appropriate
  review/ACKs."

* 'for-linus-3.6' of git://dev.laptop.org/users/dilinger/linux-olpc:
  x86: OLPC: move s/r-related EC cmds to EC driver
  Platform: OLPC: move global variables into priv struct
  Platform: OLPC: move debugfs support from x86 EC driver
  x86: OLPC: switch over to using new EC driver on x86
  Platform: OLPC: add a suspended flag to the EC driver
  Platform: OLPC: turn EC driver into a platform_driver
  Platform: OLPC: allow EC cmd to be overridden, and create a workqueue to call it
  drivers: OLPC: update various drivers to include olpc-ec.h
  Platform: OLPC: add a stub to drivers/platform/ for the OLPC EC driver
2012-08-02 11:52:39 -07:00
Konrad Rzeszutek Wilk
5bc6f9888d xen/p2m: Reserve 8MB of _brk space for P2M leafs when populating back.
When we release pages back during bootup:

Freeing  9d-100 pfn range: 99 pages freed
Freeing  9cf36-9d0d2 pfn range: 412 pages freed
Freeing  9f6bd-9f6bf pfn range: 2 pages freed
Freeing  9f714-9f7bf pfn range: 171 pages freed
Freeing  9f7e0-9f7ff pfn range: 31 pages freed
Freeing  9f800-100000 pfn range: 395264 pages freed
Released 395979 pages of unused memory

We then try to populate those pages back. In the P2M tree however
the space for those leafs must be reserved - as such we use extend_brk.
We reserve 8MB of _brk space, which means we can fit over
1048576 PFNs - which is more than we should ever need.

Without this, on certain compilation of the kernel we would hit:

(XEN) domain_crash_sync called from entry.S
(XEN) CPU:    0
(XEN) RIP:    e033:[<ffffffff818aad3b>]
(XEN) RFLAGS: 0000000000000206   EM: 1   CONTEXT: pv guest
(XEN) rax: ffffffff81a7c000   rbx: 000000000000003d   rcx: 0000000000001000
(XEN) rdx: ffffffff81a7b000   rsi: 0000000000001000   rdi: 0000000000001000
(XEN) rbp: ffffffff81801cd8   rsp: ffffffff81801c98   r8:  0000000000100000
(XEN) r9:  ffffffff81a7a000   r10: 0000000000000001   r11: 0000000000000003
(XEN) r12: 0000000000000004   r13: 0000000000000004   r14: 000000000000003d
(XEN) r15: 00000000000001e8   cr0: 000000008005003b   cr4: 00000000000006f0
(XEN) cr3: 0000000125803000   cr2: 0000000000000000
(XEN) ds: 0000   es: 0000   fs: 0000   gs: 0000   ss: e02b   cs: e033
(XEN) Guest stack trace from rsp=ffffffff81801c98:

.. which is extend_brk hitting a BUG_ON.

Interestingly enough, most of the time we are not going to hit this
b/c the _brk space is quite large (v3.5):
 ffffffff81a25000 B __brk_base
 ffffffff81e43000 B __brk_limit
= ~4MB.

vs earlier kernels (with this back-ported), the space is smaller:
 ffffffff81a25000 B __brk_base
 ffffffff81a7b000 B __brk_limit
= 344 kBytes.

where we would certainly hit this and hit extend_brk.

Note that git commit c3d93f8801
(xen: populate correct number of pages when across mem boundary (v2))
exposed this bug).

[v1: Made it 8MB of _brk space instead of 4MB per Jan's suggestion]

CC: stable@vger.kernel.org #only for 3.5
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-02 10:39:53 -04:00
Linus Torvalds
1871e845e5 Merge branch 'for-linus-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML fixes from Richard Weinberger:
 "This patch set contains mostly fixes and cleanups.  The UML tty driver
  uses now tty_port and is no longer broken like hell  :-)"

* 'for-linus-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: Add arch/x86/um to MAINTAINERS
  um: pass siginfo to guest process
  um: fix ubd_file_size for read-only files
  um: pull interrupt_end() into userspace()
  um: split syscall_trace(), pass pt_regs to it
  um: switch UPT_SET_RETURN_VALUE and regs_return_value to pt_regs
  um: set BLK_CGROUP=y in defconfig
  um: remove count_lock
  um: fully use tty_port
  um: Remove dead code
  um: remove line_ioctl()
  TTY: um/line, use tty from tty_port
  TTY: um/line, add tty_port
2012-08-01 16:45:02 -07:00
Avi Kivity
aa67f6096c KVM: VMX: Fix ds/es corruption on i386 with preemption
Commit b2da15ac26 ("KVM: VMX: Optimize %ds, %es reload") broke i386
in the following scenario:

  vcpu_load
  ...
  vmx_save_host_state
  vmx_vcpu_run
  (ds.rpl, es.rpl cleared by hardware)

  interrupt
    push ds, es  # pushes bad ds, es
    schedule
      vmx_vcpu_put
        vmx_load_host_state
          reload ds, es (with __USER_DS)
    pop ds, es  # of other thread's stack
    iret
  # other thread runs
  interrupt
    push ds, es
    schedule  # back in vcpu thread
    pop ds, es  # now with rpl=0
    iret
  ...
  vcpu_put
  resume_userspace
  iret  # clears ds, es due to mismatched rpl

(instead of resume_userspace, we might return with SYSEXIT and then
take an exception; when the exception IRETs we end up with cleared
ds, es)

Fix by avoiding the optimization on i386 and reloading ds, es on the
lightweight exit path.

Reported-by: Chris Clayron <chris2553@googlemail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-08-01 20:23:57 -03:00
H. Peter Anvin
eaf4ce6c5f x86-64, kcmp: The kcmp system call can be common
We already use the same system call handler for i386 and x86-64, there
is absolutely no reason x32 can't use the same system call, too.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: H.J. Lu <hjl.tools@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: <stable@vger.kernel.org> v3.5
Link: http://lkml.kernel.org/n/tip-vwzk3qbcr3yjyxjg2j38vgy9@git.kernel.org
2012-08-01 16:01:06 -07:00
Al Viro
a3170d2ec2 um: switch UPT_SET_RETURN_VALUE and regs_return_value to pt_regs
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2012-08-01 23:33:16 +02:00
Bruce Rogers
4b6486659a KVM: x86: apply kvmclock offset to guest wall clock time
When a guest migrates to a new host, the system time difference from the
previous host is used in the updates to the kvmclock system time visible
to the guest, resulting in a continuation of correct kvmclock based guest
timekeeping.

The wall clock component of the kvmclock provided time is currently not
updated with this same time offset. Since the Linux guest caches the
wall clock based time, this discrepency is not noticed until the guest is
rebooted. After reboot the guest's time calculations are off.

This patch adjusts the wall clock by the kvmclock_offset, resulting in
correct guest time after a reboot.

Cc: Zachary Amsden <zamsden@gmail.com>
Signed-off-by: Bruce Rogers <brogers@suse.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-08-01 17:23:50 -03:00
Andres Salomon
1fcfd08bd0 x86: OLPC: move s/r-related EC cmds to EC driver
The new EC driver calls platform-specific suspend and resume hooks; run
XO-1-specific EC commands from there, rather than deep in s/r code.  If we
attempt to run EC commands after the new EC driver has suspended, it is
refused by the ec->suspended checks.

Signed-off-by: Andres Salomon <dilinger@queued.net>
Acked-by: Paul Fox <pgf@laptop.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2012-07-31 23:27:31 -04:00
Andres Salomon
6cca83d498 Platform: OLPC: move debugfs support from x86 EC driver
There's nothing about the debugfs interface for the EC driver that is
architecture-specific, so move it into the arch-independent driver.

The code is mostly unchanged with the exception of renamed variables, coding
style changes, and API updates.

Signed-off-by: Andres Salomon <dilinger@queued.net>
Acked-by: Paul Fox <pgf@laptop.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2012-07-31 23:27:31 -04:00
Andres Salomon
85f90cf6ca x86: OLPC: switch over to using new EC driver on x86
This uses the new EC driver framework in drivers/platform/olpc.  The
XO-1 and XO-1.5-specific code is still in arch/x86, but the generic stuff
(including a new workqueue; no more running EC commands with IRQs disabled!)
can be shared with other architectures.

Signed-off-by: Andres Salomon <dilinger@queued.net>
Acked-by: Paul Fox <pgf@laptop.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2012-07-31 23:27:30 -04:00