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  1. Aug 04, 2009
    • H. Peter Anvin's avatar
      x86: fix assembly constraints in native_save_fl() · f1f029c7
      H. Peter Anvin authored 
      

From Gabe Black in bugzilla 13888:

native_save_fl is implemented as follows:

  11static inline unsigned long native_save_fl(void)
  12{
  13        unsigned long flags;
  14
  15        asm volatile("# __raw_save_flags\n\t"
  16                     "pushf ; pop %0"
  17                     : "=g" (flags)
  18                     : /* no input */
  19                     : "memory");
  20
  21        return flags;
  22}

If gcc chooses to put flags on the stack, for instance because this is
inlined into a larger function with more register pressure, the offset
of the flags variable from the stack pointer will change when the
pushf is performed. gcc doesn't attempt to understand that fact, and
address used for pop will still be the same. It will write to
somewhere near flags on the stack but not actually into it and
overwrite some other value.

I saw this happen in the ide_device_add_all function when running in a
simulator I work on. I'm assuming that some quirk of how the simulated
hardware is set up caused the code path this is on to be executed when
it normally wouldn't.

A simple fix might be to change "=g" to "=r".

Reported-by: default avatarGabe Black <spamforgabe@umich.edu>
Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
Cc: Stable Team <stable@kernel.org>
      f1f029c7
    • Borislav Petkov's avatar
      x86, msr: execute on the correct CPU subset · bab9a3da
      Borislav Petkov authored 
      

Make rdmsr_on_cpus/wrmsr_on_cpus execute on the current CPU only if it
is in the supplied bitmask.

Signed-off-by: default avatarBorislav Petkov <borislav.petkov@amd.com>
Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
      bab9a3da
    • H. Peter Anvin's avatar
      x86: Fix assert syntax in vmlinux.lds.S · d2ba8b21
      H. Peter Anvin authored 
      

Older versions of binutils did not accept the naked "ASSERT" syntax;
it is considered an expression whose value needs to be assigned to
something.

Reported-tested-and-fixed-by: default avatarJean Delvare <khali@linux-fr.org>
Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
      d2ba8b21
    • Paul Mackerras's avatar
      x86: Make 64-bit efi_ioremap use ioremap on MMIO regions · 6a7bbd57
      Paul Mackerras authored 
      

Booting current 64-bit x86 kernels on the latest Apple MacBook
(MacBook5,2) via EFI gives the following warning:

[    0.182209] ------------[ cut here ]------------
[    0.182222] WARNING: at arch/x86/mm/pageattr.c:581 __cpa_process_fault+0x44/0xa0()
[    0.182227] Hardware name: MacBook5,2
[    0.182231] CPA: called for zero pte. vaddr = ffff8800ffe00000 cpa->vaddr = ffff8800ffe00000
[    0.182236] Modules linked in:
[    0.182242] Pid: 0, comm: swapper Not tainted 2.6.31-rc4 #6
[    0.182246] Call Trace:
[    0.182254]  [<ffffffff8102c754>] ? __cpa_process_fault+0x44/0xa0
[    0.182261]  [<ffffffff81048668>] warn_slowpath_common+0x78/0xd0
[    0.182266]  [<ffffffff81048744>] warn_slowpath_fmt+0x64/0x70
[    0.182272]  [<ffffffff8102c7ec>] ? update_page_count+0x3c/0x50
[    0.182280]  [<ffffffff818d25c5>] ? phys_pmd_init+0x140/0x22e
[    0.182286]  [<ffffffff8102c754>] __cpa_process_fault+0x44/0xa0
[    0.182292]  [<ffffffff8102ce60>] __change_page_attr_set_clr+0x5f0/0xb40
[    0.182301]  [<ffffffff810d1035>] ? vm_unmap_aliases+0x175/0x190
[    0.182307]  [<ffffffff8102d4ae>] change_page_attr_set_clr+0xfe/0x3d0
[    0.182314]  [<ffffffff8102dcca>] _set_memory_uc+0x2a/0x30
[    0.182319]  [<ffffffff8102dd4b>] set_memory_uc+0x7b/0xb0
[    0.182327]  [<ffffffff818afe31>] efi_enter_virtual_mode+0x2ad/0x2c9
[    0.182334]  [<ffffffff818a1c66>] start_kernel+0x2db/0x3f4
[    0.182340]  [<ffffffff818a1289>] x86_64_start_reservations+0x99/0xb9
[    0.182345]  [<ffffffff818a1389>] x86_64_start_kernel+0xe0/0xf2
[    0.182357] ---[ end trace 4eaa2a86a8e2da22 ]---
[    0.182982] init_memory_mapping: 00000000ffffc000-0000000100000000
[    0.182993]  00ffffc000 - 0100000000 page 4k

This happens because the 64-bit version of efi_ioremap calls
init_memory_mapping for all addresses, regardless of whether they are
RAM or MMIO.  The EFI tables on this machine ask for runtime access to
some MMIO regions:

[    0.000000] EFI: mem195: type=11, attr=0x8000000000000000, range=[0x0000000093400000-0x0000000093401000) (0MB)
[    0.000000] EFI: mem196: type=11, attr=0x8000000000000000, range=[0x00000000ffc00000-0x00000000ffc40000) (0MB)
[    0.000000] EFI: mem197: type=11, attr=0x8000000000000000, range=[0x00000000ffc40000-0x00000000ffc80000) (0MB)
[    0.000000] EFI: mem198: type=11, attr=0x8000000000000000, range=[0x00000000ffc80000-0x00000000ffca4000) (0MB)
[    0.000000] EFI: mem199: type=11, attr=0x8000000000000000, range=[0x00000000ffca4000-0x00000000ffcb4000) (0MB)
[    0.000000] EFI: mem200: type=11, attr=0x8000000000000000, range=[0x00000000ffcb4000-0x00000000ffffc000) (3MB)
[    0.000000] EFI: mem201: type=11, attr=0x8000000000000000, range=[0x00000000ffffc000-0x0000000100000000) (0MB)

This arranges to pass the EFI memory type through to efi_ioremap, and
makes efi_ioremap use ioremap rather than init_memory_mapping if the
type is EFI_MEMORY_MAPPED_IO.  With this, the above warning goes away.

Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
LKML-Reference: <19062.55858.533494.471153@cargo.ozlabs.ibm.com>
Cc: Huang Ying <ying.huang@intel.com>
Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
      6a7bbd57
    • Paul Mackerras's avatar
      x86: Add quirk to make Apple MacBook5,2 use reboot=pci · 6c6c51e4
      Paul Mackerras authored 
      

The latest Apple MacBook (MacBook5,2) doesn't reboot successfully
under Linux; neither the EFI reboot method nor the default method
using the keyboard controller works (the system just hangs and doesn't
reset).  However, the method using the "PCI reset register" at 0xcf9
does work.

This adds a quirk to detect this machine via DMI and force the
reboot_type to BOOT_CF9.  With this it reboots successfully without
requiring a command-line option.  Note that the EFI code forces
reboot_type to BOOT_EFI when the machine is booted via EFI, but this
overrides that since the core_initcall runs after the EFI
initialization code.

Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
LKML-Reference: <19062.56420.501516.316181@cargo.ozlabs.ibm.com>
Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
      6c6c51e4
    • Thomas Hellstrom's avatar
      x86: Fix CPA memtype reserving in the set_pages_array*() cases · 8523acfe
      Thomas Hellstrom authored 
      The code was incorrectly reserving memtypes using the page
virtual address instead of the physical address. Furthermore,
the code was not ignoring highmem pages as it ought to.

( upstream does not pass in highmem pages yet - but upcoming
  graphics code will do it and there's no reason to not handle
  this properly in the CPA APIs.)

Fixes: http://bugzilla.kernel.org/show_bug.cgi?id=13884



Signed-off-by: default avatarThomas Hellstrom <thellstrom@vmware.com>
Acked-by: default avatarSuresh Siddha <suresh.b.siddha@intel.com>
Cc: <stable@kernel.org>
Cc: dri-devel@lists.sourceforge.net
Cc: venkatesh.pallipadi@intel.com
LKML-Reference: <1249284345-7654-1-git-send-email-thellstrom@vmware.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      8523acfe
  3. Jul 31, 2009
    • Pallipadi, Venkatesh's avatar
      x86, pat: Fix set_memory_wc related corruption · bdc6340f
      Pallipadi, Venkatesh authored 
      Changeset 3869c4aa
that went in after 2.6.30-rc1 was a seemingly small change to _set_memory_wc()
to make it complaint with SDM requirements. But, introduced a nasty bug, which
can result in crash and/or strange corruptions when set_memory_wc is used.
One such crash reported here
http://lkml.org/lkml/2009/7/30/94



Actually, that changeset introduced two bugs.
* change_page_attr_set() takes &addr as first argument and can the addr value
  might have changed on return, even for single page change_page_attr_set()
  call. That will make the second change_page_attr_set() in this routine
  operate on unrelated addr, that can eventually cause strange corruptions
  and bad page state crash.
* The second change_page_attr_set() call, before setting _PAGE_CACHE_WC, should
  clear the earlier _PAGE_CACHE_UC_MINUS, as otherwise cache attribute will not
  be WC (will be UC instead).

The patch below fixes both these problems. Sending a single patch to fix both
the problems, as the change is to the same line of code. The change to have a
addr_copy is not very clean. But, it is simpler than making more changes
through various routines in pageattr.c.

A huge thanks to Jerome for reporting this problem and providing a simple test
case that helped us root cause the problem.

Reported-by: default avatarJerome Glisse <glisse@freedesktop.org>
Signed-off-by: default avatarVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: default avatarSuresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <20090730214319.GA1889@linux-os.sc.intel.com>
Acked-by: default avatarDave Airlie <airlied@redhat.com>
Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
      bdc6340f
  5. Jul 28, 2009
  7. Jul 27, 2009
  9. Jul 26, 2009