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  1. 21 2月, 2013 1 次提交
  3. 14 2月, 2013 1 次提交
    • S
      efi: Clear EFI_RUNTIME_SERVICES rather than EFI_BOOT by "noefi" boot parameter · 1de63d60
      由 Satoru Takeuchi 提交于 
      There was a serious problem in samsung-laptop that its platform driver is
designed to run under BIOS and running under EFI can cause the machine to
become bricked or can cause Machine Check Exceptions.

    Discussion about this problem:
    https://bugs.launchpad.net/ubuntu-cdimage/+bug/1040557
    https://bugzilla.kernel.org/show_bug.cgi?id=47121

    The patches to fix this problem:
    efi: Make 'efi_enabled' a function to query EFI facilities
    83e68189

    samsung-laptop: Disable on EFI hardware
    e0094244

Unfortunately this problem comes back again if users specify "noefi" option.
This parameter clears EFI_BOOT and that driver continues to run even if running
under EFI. Refer to the document, this parameter should clear
EFI_RUNTIME_SERVICES instead.

Documentation/kernel-parameters.txt:
===============================================================================
...
	noefi		[X86] Disable EFI runtime services support.
...
===============================================================================

Documentation/x86/x86_64/uefi.txt:
===============================================================================
...
- If some or all EFI runtime services don't work, you can try following
  kernel command line parameters to turn off some or all EFI runtime
  services.
	noefi		turn off all EFI runtime services
...
===============================================================================
Signed-off-by: NSatoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Link: http://lkml.kernel.org/r/511C2C04.2070108@jp.fujitsu.com
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
      1de63d60
  5. 31 1月, 2013 1 次提交
    • M
      efi: Make 'efi_enabled' a function to query EFI facilities · 83e68189
      由 Matt Fleming 提交于 
      Originally 'efi_enabled' indicated whether a kernel was booted from
EFI firmware. Over time its semantics have changed, and it now
indicates whether or not we are booted on an EFI machine with
bit-native firmware, e.g. 64-bit kernel with 64-bit firmware.

The immediate motivation for this patch is the bug report at,

    https://bugs.launchpad.net/ubuntu-cdimage/+bug/1040557

which details how running a platform driver on an EFI machine that is
designed to run under BIOS can cause the machine to become
bricked. Also, the following report,

    https://bugzilla.kernel.org/show_bug.cgi?id=47121

details how running said driver can also cause Machine Check
Exceptions. Drivers need a new means of detecting whether they're
running on an EFI machine, as sadly the expression,

    if (!efi_enabled)

hasn't been a sufficient condition for quite some time.

Users actually want to query 'efi_enabled' for different reasons -
what they really want access to is the list of available EFI
facilities.

For instance, the x86 reboot code needs to know whether it can invoke
the ResetSystem() function provided by the EFI runtime services, while
the ACPI OSL code wants to know whether the EFI config tables were
mapped successfully. There are also checks in some of the platform
driver code to simply see if they're running on an EFI machine (which
would make it a bad idea to do BIOS-y things).

This patch is a prereq for the samsung-laptop fix patch.

Cc: David Airlie <airlied@linux.ie>
Cc: Corentin Chary <corentincj@iksaif.net>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Olof Johansson <olof@lixom.net>
Cc: Peter Jones <pjones@redhat.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Steve Langasek <steve.langasek@canonical.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Konrad Rzeszutek Wilk <konrad@kernel.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: <stable@vger.kernel.org>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
      83e68189
  7. 25 1月, 2013 2 次提交
  9. 18 1月, 2013 1 次提交
    • N
      efi, x86: Pass a proper identity mapping in efi_call_phys_prelog · b8f2c21d
      由 Nathan Zimmer 提交于 
      Update efi_call_phys_prelog to install an identity mapping of all available
memory.  This corrects a bug on very large systems with more then 512 GB in
which bios would not be able to access addresses above not in the mapping.

The result is a crash that looks much like this.

BUG: unable to handle kernel paging request at 000000effd870020
IP: [<0000000078bce331>] 0x78bce330
PGD 0
Oops: 0000 [#1] SMP
Modules linked in:
CPU 0
Pid: 0, comm: swapper/0 Tainted: G        W    3.8.0-rc1-next-20121224-medusa_ntz+ #2 Intel Corp. Stoutland Platform
RIP: 0010:[<0000000078bce331>]  [<0000000078bce331>] 0x78bce330
RSP: 0000:ffffffff81601d28  EFLAGS: 00010006
RAX: 0000000078b80e18 RBX: 0000000000000004 RCX: 0000000000000004
RDX: 0000000078bcf958 RSI: 0000000000002400 RDI: 8000000000000000
RBP: 0000000078bcf760 R08: 000000effd870000 R09: 0000000000000000
R10: 0000000000000000 R11: 00000000000000c3 R12: 0000000000000030
R13: 000000effd870000 R14: 0000000000000000 R15: ffff88effd870000
FS:  0000000000000000(0000) GS:ffff88effe400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000effd870020 CR3: 000000000160c000 CR4: 00000000000006b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process swapper/0 (pid: 0, threadinfo ffffffff81600000, task ffffffff81614400)
Stack:
 0000000078b80d18 0000000000000004 0000000078bced7b ffff880078b81fff
 0000000000000000 0000000000000082 0000000078bce3a8 0000000000002400
 0000000060000202 0000000078b80da0 0000000078bce45d ffffffff8107cb5a
Call Trace:
 [<ffffffff8107cb5a>] ? on_each_cpu+0x77/0x83
 [<ffffffff8102f4eb>] ? change_page_attr_set_clr+0x32f/0x3ed
 [<ffffffff81035946>] ? efi_call4+0x46/0x80
 [<ffffffff816c5abb>] ? efi_enter_virtual_mode+0x1f5/0x305
 [<ffffffff816aeb24>] ? start_kernel+0x34a/0x3d2
 [<ffffffff816ae5ed>] ? repair_env_string+0x60/0x60
 [<ffffffff816ae2be>] ? x86_64_start_reservations+0xba/0xc1
 [<ffffffff816ae120>] ? early_idt_handlers+0x120/0x120
 [<ffffffff816ae419>] ? x86_64_start_kernel+0x154/0x163
Code:  Bad RIP value.
RIP  [<0000000078bce331>] 0x78bce330
 RSP <ffffffff81601d28>
CR2: 000000effd870020
---[ end trace ead828934fef5eab ]---

Cc: stable@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NNathan Zimmer <nzimmer@sgi.com>
Signed-off-by: NRobin Holt <holt@sgi.com>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
      b8f2c21d
  11. 16 12月, 2012 1 次提交
  13. 15 11月, 2012 1 次提交
  15. 30 10月, 2012 2 次提交
    • J
      x86-64/efi: Use EFI to deal with platform wall clock (again) · bd52276f
      由 Jan Beulich 提交于 
      Other than ix86, x86-64 on EFI so far didn't set the
{g,s}et_wallclock accessors to the EFI routines, thus
incorrectly using raw RTC accesses instead.

Simply removing the #ifdef around the respective code isn't
enough, however: While so far early get-time calls were done in
physical mode, this doesn't work properly for x86-64, as virtual
addresses would still need to be set up for all runtime regions
(which wasn't the case on the system I have access to), so
instead the patch moves the call to efi_enter_virtual_mode()
ahead (which in turn allows to drop all code related to calling
efi-get-time in physical mode).

Additionally the earlier calling of efi_set_executable()
requires the CPA code to cope, i.e. during early boot it must be
avoided to call cpa_flush_array(), as the first thing this
function does is a BUG_ON(irqs_disabled()).

Also make the two EFI functions in question here static -
they're not being referenced elsewhere.

History:

    This commit was originally merged as bacef661 ("x86-64/efi:
    Use EFI to deal with platform wall clock") but it resulted in some
    ASUS machines no longer booting due to a firmware bug, and so was
    reverted in f026cfa8. A pre-emptive fix for the buggy ASUS
    firmware was merged in 03a1c254975e ("x86, efi: 1:1 pagetable
    mapping for virtual EFI calls") so now this patch can be
    reapplied.
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Tested-by: NMatt Fleming <matt.fleming@intel.com>
Acked-by: NMatthew Garrett <mjg@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com> [added commit history]
      bd52276f
    • M
      x86, efi: 1:1 pagetable mapping for virtual EFI calls · 185034e7
      由 Matt Fleming 提交于 
      Some firmware still needs a 1:1 (virt->phys) mapping even after we've
called SetVirtualAddressMap(). So install the mapping alongside our
existing kernel mapping whenever we make EFI calls in virtual mode.

This bug was discovered on ASUS machines where the firmware
implementation of GetTime() accesses the RTC device via physical
addresses, even though that's bogus per the UEFI spec since we've
informed the firmware via SetVirtualAddressMap() that the boottime
memory map is no longer valid.

This bug seems to be present in a lot of consumer devices, so there's
not a lot we can do about this spec violation apart from workaround
it.

Cc: JérômeCarretero <cJ-ko@zougloub.eu>
Cc: Vasco Dias <rafa.vasco@gmail.com>
Acked-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
      185034e7
  17. 26 10月, 2012 1 次提交
  19. 24 10月, 2012 1 次提交
    • M
      x86/efi: Fix oops caused by incorrect set_memory_uc() usage · 3e8fa263
      由 Matt Fleming 提交于 
      Calling __pa() with an ioremap'd address is invalid. If we
encounter an efi_memory_desc_t without EFI_MEMORY_WB set in
->attribute we currently call set_memory_uc(), which in turn
calls __pa() on a potentially ioremap'd address.

On CONFIG_X86_32 this results in the following oops:

  BUG: unable to handle kernel paging request at f7f22280
  IP: [<c10257b9>] reserve_ram_pages_type+0x89/0x210
  *pdpt = 0000000001978001 *pde = 0000000001ffb067 *pte = 0000000000000000
  Oops: 0000 [#1] PREEMPT SMP
  Modules linked in:

  Pid: 0, comm: swapper Not tainted 3.0.0-acpi-efi-0805 #3
   EIP: 0060:[<c10257b9>] EFLAGS: 00010202 CPU: 0
   EIP is at reserve_ram_pages_type+0x89/0x210
   EAX: 0070e280 EBX: 38714000 ECX: f7814000 EDX: 00000000
   ESI: 00000000 EDI: 38715000 EBP: c189fef0 ESP: c189fea8
   DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
  Process swapper (pid: 0, ti=c189e000 task=c18bbe60 task.ti=c189e000)
  Stack:
   80000200 ff108000 00000000 c189ff00 00038714 00000000 00000000 c189fed0
   c104f8ca 00038714 00000000 00038715 00000000 00000000 00038715 00000000
   00000010 38715000 c189ff48 c1025aff 38715000 00000000 00000010 00000000
  Call Trace:
   [<c104f8ca>] ? page_is_ram+0x1a/0x40
   [<c1025aff>] reserve_memtype+0xdf/0x2f0
   [<c1024dc9>] set_memory_uc+0x49/0xa0
   [<c19334d0>] efi_enter_virtual_mode+0x1c2/0x3aa
   [<c19216d4>] start_kernel+0x291/0x2f2
   [<c19211c7>] ? loglevel+0x1b/0x1b
   [<c19210bf>] i386_start_kernel+0xbf/0xc8

The only time we can call set_memory_uc() for a memory region is
when it is part of the direct kernel mapping. For the case where
we ioremap a memory region we must leave it alone.

This patch reimplements the fix from e8c71062 ("x86, efi:
Calling __pa() with an ioremap()ed address is invalid") which
was reverted in e1ad783b because it caused a regression on
some MacBooks (they hung at boot). The regression was caused
because the commit only marked EFI_RUNTIME_SERVICES_DATA as
E820_RESERVED_EFI, when it should have marked all regions that
have the EFI_MEMORY_RUNTIME attribute.

Despite first impressions, it's not possible to use
ioremap_cache() to map all cached memory regions on
CONFIG_X86_64 because of the way that the memory map might be
configured as detailed in the following bug report,

	https://bugzilla.redhat.com/show_bug.cgi?id=748516

e.g. some of the EFI memory regions *need* to be mapped as part
of the direct kernel mapping.
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Huang Ying <huang.ying.caritas@gmail.com>
Cc: Keith Packard <keithp@keithp.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1350649546-23541-1-git-send-email-matt@console-pimps.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>
      3e8fa263
  21. 30 9月, 2012 3 次提交
  23. 17 9月, 2012 1 次提交
  25. 15 8月, 2012 1 次提交
  27. 06 6月, 2012 1 次提交
    • J
      x86-64/efi: Use EFI to deal with platform wall clock · bacef661
      由 Jan Beulich 提交于 
      Other than ix86, x86-64 on EFI so far didn't set the
{g,s}et_wallclock accessors to the EFI routines, thus
incorrectly using raw RTC accesses instead.

Simply removing the #ifdef around the respective code isn't
enough, however: While so far early get-time calls were done in
physical mode, this doesn't work properly for x86-64, as virtual
addresses would still need to be set up for all runtime regions
(which wasn't the case on the system I have access to), so
instead the patch moves the call to efi_enter_virtual_mode()
ahead (which in turn allows to drop all code related to calling
efi-get-time in physical mode).

Additionally the earlier calling of efi_set_executable()
requires the CPA code to cope, i.e. during early boot it must be
avoided to call cpa_flush_array(), as the first thing this
function does is a BUG_ON(irqs_disabled()).

Also make the two EFI functions in question here static -
they're not being referenced elsewhere.
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Tested-by: NMatt Fleming <matt.fleming@intel.com>
Acked-by: NMatthew 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/4FBFBF5F020000780008637F@nat28.tlf.novell.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      bacef661
  29. 24 2月, 2012 5 次提交
  31. 13 12月, 2011 1 次提交
  33. 10 12月, 2011 1 次提交
    • M
      x86, efi: Make efi_call_phys_{prelog,epilog} CONFIG_RELOCATABLE-aware · 6d3e32e6
      由 Matt Fleming 提交于 
      efi_call_phys_prelog() sets up a 1:1 mapping of the physical address
range in swapper_pg_dir. Instead of replacing then restoring entries
in swapper_pg_dir we should be using initial_page_table which already
contains the 1:1 mapping.

It's safe to blindly switch back to swapper_pg_dir in the epilog
because the physical EFI routines are only called before
efi_enter_virtual_mode(), e.g. before any user processes have been
forked. Therefore, we don't need to track which pgd was in %cr3 when
we entered the prelog.

The previous code actually contained a bug because it assumed that the
kernel was loaded at a physical address within the first 8MB of ram,
usually at 0x100000. However, this isn't the case with a
CONFIG_RELOCATABLE=y kernel which could have been loaded anywhere in
the physical address space.

Also delete the ancient (and bogus) comments about the page table
being restored after the lock is released. There is no locking.

Cc: Matthew Garrett <mjg@redhat.com>
Cc: Darrent Hart <dvhart@linux.intel.com>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1323346250.3894.74.camel@mfleming-mobl1.ger.corp.intel.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>
      6d3e32e6
  35. 09 12月, 2011 1 次提交
    • M
      x86, efi: Calling __pa() with an ioremap()ed address is invalid · e8c71062
      由 Matt Fleming 提交于 
      If we encounter an efi_memory_desc_t without EFI_MEMORY_WB set
in ->attribute we currently call set_memory_uc(), which in turn
calls __pa() on a potentially ioremap'd address.

On CONFIG_X86_32 this is invalid, resulting in the following
oops on some machines:

  BUG: unable to handle kernel paging request at f7f22280
  IP: [<c10257b9>] reserve_ram_pages_type+0x89/0x210
  [...]

  Call Trace:
   [<c104f8ca>] ? page_is_ram+0x1a/0x40
   [<c1025aff>] reserve_memtype+0xdf/0x2f0
   [<c1024dc9>] set_memory_uc+0x49/0xa0
   [<c19334d0>] efi_enter_virtual_mode+0x1c2/0x3aa
   [<c19216d4>] start_kernel+0x291/0x2f2
   [<c19211c7>] ? loglevel+0x1b/0x1b
   [<c19210bf>] i386_start_kernel+0xbf/0xc8

A better approach to this problem is to map the memory region
with the correct attributes from the start, instead of modifying
it after the fact. The uncached case can be handled by
ioremap_nocache() and the cached by ioremap_cache().

Despite first impressions, it's not possible to use
ioremap_cache() to map all cached memory regions on
CONFIG_X86_64 because EFI_RUNTIME_SERVICES_DATA regions really
don't like being mapped into the vmalloc space, as detailed in
the following bug report,

	https://bugzilla.redhat.com/show_bug.cgi?id=748516

Therefore, we need to ensure that any EFI_RUNTIME_SERVICES_DATA
regions are covered by the direct kernel mapping table on
CONFIG_X86_64. To accomplish this we now map E820_RESERVED_EFI
regions via the direct kernel mapping with the initial call to
init_memory_mapping() in setup_arch(), whereas previously these
regions wouldn't be mapped if they were after the last E820_RAM
region until efi_ioremap() was called. Doing it this way allows
us to delete efi_ioremap() completely.
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Huang Ying <huang.ying.caritas@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1321621751-3650-1-git-send-email-matt@console-pimps.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>
      e8c71062
  37. 05 12月, 2011 1 次提交
  39. 01 11月, 2011 2 次提交
    • P
      x86: efi_32.c is implicitly getting asm/desc.h via module.h · 783ac47c
      由 Paul Gortmaker 提交于 
      We want to clean up the chain of includes stumbling through
module.h, and when we do that, we'll see:

  CC      arch/x86/platform/efi/efi_32.o
  efi/efi_32.c: In function ‘efi_call_phys_prelog’:
  efi/efi_32.c:80: error: implicit declaration of function ‘get_cpu_gdt_table’
  efi/efi_32.c:82: error: implicit declaration of function ‘load_gdt’
  make[4]: *** [arch/x86/platform/efi/efi_32.o] Error 1

Include asm/desc.h so that there are no implicit include assumptions.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
      783ac47c
    • P
      x86: Fix files explicitly requiring export.h for EXPORT_SYMBOL/THIS_MODULE · 69c60c88
      由 Paul Gortmaker 提交于 
      These files were implicitly getting EXPORT_SYMBOL via device.h
which was including module.h, but that will be fixed up shortly.

By fixing these now, we can avoid seeing things like:

arch/x86/kernel/rtc.c:29: warning: type defaults to ‘int’ in declaration of ‘EXPORT_SYMBOL’
arch/x86/kernel/pci-dma.c:20: warning: type defaults to ‘int’ in declaration of ‘EXPORT_SYMBOL’
arch/x86/kernel/e820.c:69: warning: type defaults to ‘int’ in declaration of ‘EXPORT_SYMBOL_GPL’

[ with input from Randy Dunlap <rdunlap@xenotime.net> and also
  from Stephen Rothwell <sfr@canb.auug.org.au> ]
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
      69c60c88
  41. 21 7月, 2011 1 次提交
  43. 15 7月, 2011 1 次提交
  45. 14 7月, 2011 1 次提交
  47. 07 7月, 2011 1 次提交
  49. 05 7月, 2011 1 次提交
  51. 19 6月, 2011 1 次提交
  53. 07 6月, 2011 2 次提交
  55. 26 5月, 2011 1 次提交
    • M
      x86, efi: Retain boot service code until after switching to virtual mode · 916f676f
      由 Matthew Garrett 提交于 
      UEFI stands for "Unified Extensible Firmware Interface", where "Firmware"
is an ancient African word meaning "Why do something right when you can
do it so wrong that children will weep and brave adults will cower before
you", and "UEI" is Celtic for "We missed DOS so we burned it into your
ROMs". The UEFI specification provides for runtime services (ie, another
way for the operating system to be forced to depend on the firmware) and
we rely on these for certain trivial tasks such as setting up the
bootloader. But some hardware fails to work if we attempt to use these
runtime services from physical mode, and so we have to switch into virtual
mode. So far so dreadful.

The specification makes it clear that the operating system is free to do
whatever it wants with boot services code after ExitBootServices() has been
called. SetVirtualAddressMap() can't be called until ExitBootServices() has
been. So, obviously, a whole bunch of EFI implementations call into boot
services code when we do that. Since we've been charmingly naive and
trusted that the specification may be somehow relevant to the real world,
we've already stuffed a picture of a penguin or something in that address
space. And just to make things more entertaining, we've also marked it
non-executable.

This patch allocates the boot services regions during EFI init and makes
sure that they're executable. Then, after SetVirtualAddressMap(), it
discards them and everyone lives happily ever after. Except for the ones
who have to work on EFI, who live sad lives haunted by the knowledge that
someone's eventually going to write yet another firmware specification.

[ hpa: adding this to urgent with a stable tag since it fixes currently-broken
  hardware.  However, I do not know what the dependencies are and so I do
  not know which -stable versions this may be a candidate for. ]
Signed-off-by: NMatthew Garrett <mjg@redhat.com>
Link: http://lkml.kernel.org/r/1306331593-28715-1-git-send-email-mjg@redhat.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: <stable@kernel.org>
      916f676f
  57. 10 5月, 2011 2 次提交