linux-toradex.git/arch/x86, branch v3.9.8

x86: Fix section mismatch on load_ucode_ap

2013-06-27T17:38:46+00:00

commit 949785996ec2250fa958fc3a924e5186e9a8fa2c upstream.

We are in the process of removing all the __cpuinit annotations.
While working on making that change, an existing problem was
made evident:

  WARNING: arch/x86/kernel/built-in.o(.text+0x198f2): Section mismatch
  in reference from the function cpu_init() to the function
  .init.text:load_ucode_ap()   The function cpu_init() references
  the function __init load_ucode_ap().  This is often because cpu_init
  lacks a __init annotation or the annotation of load_ucode_ap is wrong.

This now appears because in my working tree, cpu_init() is no longer
tagged as __cpuinit, and so the audit picks up the mismatch.  The 2nd
hypothesis from the audit is the correct one, as there was an incorrect
__init tag on the prototype in the header (but __cpuinit was used on
the function itself.)

The audit is telling us that the prototype's __init annotation took
effect and the function did land in the .init.text section.  Checking
with objdump on a mainline tree that still has __cpuinit shows that
the __cpuinit on the function takes precedence over the __init on the
prototype, but that won't be true once we make __cpuinit a no-op.

Even though we are removing __cpuinit, we temporarily align both
the function and the prototype on __cpuinit so that the changeset
can be applied to stable trees  if desired.

[ hpa: build fix only, no object code change ]

Signed-off-by: Paul Gortmaker 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: "H. Peter Anvin" 
Link: http://lkml.kernel.org/r/1371654926-11729-1-git-send-email-paul.gortmaker@windriver.com
Signed-off-by: H. Peter Anvin 
Signed-off-by: Greg Kroah-Hartman

x86: fix build error and kconfig for ia32_emulation and binfmt

2013-06-27T17:38:46+00:00

commit d1603990ea626668c78527376d9ec084d634202d upstream.

Fix kconfig warning and build errors on x86_64 by selecting BINFMT_ELF
when COMPAT_BINFMT_ELF is being selected.

warning: (IA32_EMULATION) selects COMPAT_BINFMT_ELF which has unmet direct dependencies (COMPAT && BINFMT_ELF)

fs/built-in.o: In function `elf_core_dump':
compat_binfmt_elf.c:(.text+0x3e093): undefined reference to `elf_core_extra_phdrs'
compat_binfmt_elf.c:(.text+0x3ebcd): undefined reference to `elf_core_extra_data_size'
compat_binfmt_elf.c:(.text+0x3eddd): undefined reference to `elf_core_write_extra_phdrs'
compat_binfmt_elf.c:(.text+0x3f004): undefined reference to `elf_core_write_extra_data'

[ hpa: This was sent to me for -next but it is a low risk build fix ]

Signed-off-by: Randy Dunlap 
Link: http://lkml.kernel.org/r/51C0B614.5000708@infradead.org
Signed-off-by: H. Peter Anvin 
Signed-off-by: Greg Kroah-Hartman

x86, mtrr: Fix original mtrr range get for mtrr_cleanup

2013-06-27T17:38:46+00:00

commit d8d386c10630d8f7837700f4c466443d49e12cc0 upstream.

Joshua reported: Commit cd7b304dfaf1 (x86, range: fix missing merge
during add range) broke mtrr cleanup on his setup in 3.9.5.
corresponding commit in upstream is fbe06b7bae7c.

  *BAD*gran_size: 64K chunk_size: 16M num_reg: 6 lose cover RAM: -0G

https://bugzilla.kernel.org/show_bug.cgi?id=59491

So it rejects new var mtrr layout.

It turns out we have some problem with initial mtrr range retrieval.
The current sequence is:
	x86_get_mtrr_mem_range
		==> bunchs of add_range_with_merge
		==> bunchs of subract_range
		==> clean_sort_range
	add_range_with_merge for [0,1M)
	sort_range()

add_range_with_merge could have blank slots, so we can not just
sort only, that will have final result have extra blank slot in head.

So move that calling add_range_with_merge for [0,1M), with that we
could avoid extra clean_sort_range calling.

Reported-by: Joshua Covington 
Tested-by: Joshua Covington 
Signed-off-by: Yinghai Lu 
Link: http://lkml.kernel.org/r/1371154622-8929-2-git-send-email-yinghai@kernel.org
Signed-off-by: H. Peter Anvin 
Signed-off-by: Greg Kroah-Hartman

KVM: x86: remove vcpu's CPL check in host-invoked XCR set

2013-06-27T17:38:44+00:00

commit 764bcbc5a6d7a2f3e75c9f0e4caa984e2926e346 upstream.

__kvm_set_xcr function does the CPL check when set xcr. __kvm_set_xcr is
called in two flows, one is invoked by guest, call stack shown as below,

  handle_xsetbv(or xsetbv_interception)
    kvm_set_xcr
      __kvm_set_xcr

the other one is invoked by host, for example during system reset:

  kvm_arch_vcpu_ioctl
    kvm_vcpu_ioctl_x86_set_xcrs
      __kvm_set_xcr

The former does need the CPL check, but the latter does not.

Signed-off-by: Zhang Haoyu 
[Tweaks to commit message. - Paolo]
Signed-off-by: Paolo Bonzini 
Signed-off-by: Greg Kroah-Hartman

x86: kvmclock: zero initialize pvclock shared memory area

2013-06-27T17:38:44+00:00

commit 07868fc6aaf57847b0f3a3d53086b7556eb83f4a upstream.

kernel might hung in pvclock_clocksource_read() due to
uninitialized memory might contain odd version value in
following cycle:

        do {
                version = __pvclock_read_cycles(src, &ret, &flags);
        } while ((src->version & 1) || version != src->version);

if secondary kvmclock is accessed before it's registered with kvm.

Clear garbage in pvclock shared memory area right after it's
allocated to avoid this issue.

Ref: https://bugzilla.kernel.org/show_bug.cgi?id=59521
Signed-off-by: Igor Mammedov 
[See BZ for analysis.  We may want a different fix for 3.11, but
 this is the safest for now - Paolo]
Signed-off-by: Paolo Bonzini 
Signed-off-by: Greg Kroah-Hartman

x86/efi: Fix dummy variable buffer allocation

2013-06-27T17:38:44+00:00

commit b8cb62f82103083a6e8fa5470bfe634a2c06514d upstream.

1. Check for allocation failure
2. Clear the buffer contents, as they may actually be written to flash
3. Don't leak the buffer

Compile-tested only.

[ Tested successfully on my buggy ASUS machine - Matt ]

Signed-off-by: Ben Hutchings 
Signed-off-by: Matt Fleming 
Signed-off-by: Greg Kroah-Hartman

Modify UEFI anti-bricking code

2013-06-20T19:01:32+00:00

commit f8b8404337de4e2466e2e1139ea68b1f8295974f upstream.

This patch reworks the UEFI anti-bricking code, including an effective
reversion of cc5a080c and 31ff2f20. It turns out that calling
QueryVariableInfo() from boot services results in some firmware
implementations jumping to physical addresses even after entering virtual
mode, so until we have 1:1 mappings for UEFI runtime space this isn't
going to work so well.

Reverting these gets us back to the situation where we'd refuse to create
variables on some systems because they classify deleted variables as "used"
until the firmware triggers a garbage collection run, which they won't do
until they reach a lower threshold. This results in it being impossible to
install a bootloader, which is unhelpful.

Feedback from Samsung indicates that the firmware doesn't need more than
5KB of storage space for its own purposes, so that seems like a reasonable
threshold. However, there's still no guarantee that a platform will attempt
garbage collection merely because it drops below this threshold. It seems
that this is often only triggered if an attempt to write generates a
genuine EFI_OUT_OF_RESOURCES error. We can force that by attempting to
create a variable larger than the remaining space. This should fail, but if
it somehow succeeds we can then immediately delete it.

I've tested this on the UEFI machines I have available, but I don't have
a Samsung and so can't verify that it avoids the bricking problem.

Signed-off-by: Matthew Garrett 
Signed-off-by: Lee, Chun-Y  [ dummy variable cleanup ]
Signed-off-by: Matt Fleming 
Signed-off-by: Greg Kroah-Hartman

x86: Fix typo in kexec register clearing

2013-06-20T19:01:31+00:00

commit c8a22d19dd238ede87aa0ac4f7dbea8da039b9c1 upstream.

Fixes a typo in register clearing code. Thanks to PaX Team for fixing
this originally, and James Troup for pointing it out.

Signed-off-by: Kees Cook 
Link: http://lkml.kernel.org/r/20130605184718.GA8396@www.outflux.net
Cc: PaX Team 
Signed-off-by: H. Peter Anvin 
Signed-off-by: Greg Kroah-Hartman

x86: Fix adjust_range_size_mask calling position

2013-06-20T19:01:31+00:00

commit 7de3d66b1387ddf5a37d9689e5eb8510fb75c765 upstream.

Commit

    8d57470d x86, mm: setup page table in top-down

causes a kernel panic while setting mem=2G.

     [mem 0x00000000-0x000fffff] page 4k
     [mem 0x7fe00000-0x7fffffff] page 1G
     [mem 0x7c000000-0x7fdfffff] page 1G
     [mem 0x00100000-0x001fffff] page 4k
     [mem 0x00200000-0x7bffffff] page 2M

for last entry is not what we want, we should have
     [mem 0x00200000-0x3fffffff] page 2M
     [mem 0x40000000-0x7bffffff] page 1G

Actually we merge the continuous ranges with same page size too early.
in this case, before merging we have
     [mem 0x00200000-0x3fffffff] page 2M
     [mem 0x40000000-0x7bffffff] page 2M
after merging them, will get
     [mem 0x00200000-0x7bffffff] page 2M
even we can use 1G page to map
     [mem 0x40000000-0x7bffffff]

that will cause problem, because we already map
     [mem 0x7fe00000-0x7fffffff] page 1G
     [mem 0x7c000000-0x7fdfffff] page 1G
with 1G page, aka [0x40000000-0x7fffffff] is mapped with 1G page already.
During phys_pud_init() for [0x40000000-0x7bffffff], it will not
reuse existing that pud page, and allocate new one then try to use
2M page to map it instead, as page_size_mask does not include
PG_LEVEL_1G. At end will have [7c000000-0x7fffffff] not mapped, loop
in phys_pmd_init stop mapping at 0x7bffffff.

That is right behavoir, it maps exact range with exact page size that
we ask, and we should explicitly call it to map [7c000000-0x7fffffff]
before or after mapping 0x40000000-0x7bffffff.
Anyway we need to make sure ranges' page_size_mask correct and consistent
after split_mem_range for each range.

Fix that by calling adjust_range_size_mask before merging range
with same page size.

-v2: update change log.
-v3: add more explanation why [7c000000-0x7fffffff] is not mapped, and
    it causes panic.

Bisected-by: "Xie, ChanglongX" 
Bisected-by: Yuanhan Liu 
Reported-and-tested-by: Yuanhan Liu 
Signed-off-by: Yinghai Lu 
Link: http://lkml.kernel.org/r/1370015587-20835-1-git-send-email-yinghai@kernel.org
Signed-off-by: H. Peter Anvin 
Signed-off-by: Greg Kroah-Hartman

xen/smp: Fixup NOHZ per cpu data when onlining an offline CPU.

2013-06-13T17:49:50+00:00

commit 466318a87f28cb3ba0d08a3b7ef1a37ae73d5aa7 upstream.

The xen_play_dead is an undead function. When the vCPU is told to
offline it ends up calling xen_play_dead wherin it calls the
VCPUOP_down hypercall which offlines the vCPU. However, when the
vCPU is onlined back, it resumes execution right after
VCPUOP_down hypercall.

That was OK (albeit the API for play_dead assumes that the CPU
stays dead and never returns) but with commit 4b0c0f294
(tick: Cleanup NOHZ per cpu data on cpu down) that is no longer safe
as said commit resets the ts->inidle which at the start of the
cpu_idle loop was set.

The net effect is that we get this warn:

Broke affinity for irq 16
installing Xen timer for CPU 1
cpu 1 spinlock event irq 48
------------[ cut here ]------------
WARNING: at /home/konrad/linux-linus/kernel/time/tick-sched.c:935 tick_nohz_idle_exit+0x195/0x1b0()
Modules linked in: dm_multipath dm_mod xen_evtchn iscsi_boot_sysfs
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 3.10.0-rc3upstream-00068-gdcdbe33 #1
Hardware name: BIOSTAR Group N61PB-M2S/N61PB-M2S, BIOS 6.00 PG 09/03/2009
 ffffffff8193b448 ffff880039da5e60 ffffffff816707c8 ffff880039da5ea0
 ffffffff8108ce8b ffff880039da4010 ffff88003fa8e500 ffff880039da4010
 0000000000000001 ffff880039da4000 ffff880039da4010 ffff880039da5eb0
Call Trace:
 [] dump_stack+0x19/0x1b
 [] warn_slowpath_common+0x6b/0xa0
 [] warn_slowpath_null+0x15/0x20
 [] tick_nohz_idle_exit+0x195/0x1b0
 [] cpu_startup_entry+0x205/0x250
 [] cpu_bringup_and_idle+0x13/0x15
---[ end trace 915c8c486004dda1 ]---

b/c ts_inidle is set to zero. Thomas suggested that we just add a workaround
to call tick_nohz_idle_enter before returning from xen_play_dead() - and
that is what this patch does and fixes the issue.

We also add the stable part b/c git commit 4b0c0f294 is on the stable
tree.

Suggested-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Konrad Rzeszutek Wilk