linux-stable.git/arch/x86/platform, branch linux-4.4.y

efi/x86: Map the entire EFI vendor string before copying it

2020-02-28T14:38:53+00:00

[ Upstream commit ffc2760bcf2dba0dbef74013ed73eea8310cc52c ]

Fix a couple of issues with the way we map and copy the vendor string:
- we map only 2 bytes, which usually works since you get at least a
  page, but if the vendor string happens to cross a page boundary,
  a crash will result
- only call early_memunmap() if early_memremap() succeeded, or we will
  call it with a NULL address which it doesn't like,
- while at it, switch to early_memremap_ro(), and array indexing rather
  than pointer dereferencing to read the CHAR16 characters.

Signed-off-by: Ard Biesheuvel 
Cc: Andy Lutomirski 
Cc: Ard Biesheuvel 
Cc: Arvind Sankar 
Cc: Matthew Garrett 
Cc: linux-efi@vger.kernel.org
Fixes: 5b83683f32b1 ("x86: EFI runtime service support")
Link: https://lkml.kernel.org/r/20200103113953.9571-5-ardb@kernel.org
Signed-off-by: Ingo Molnar 
Signed-off-by: Sasha Levin

efi/x86: Do not clean dummy variable in kexec path

2019-11-06T11:09:14+00:00

[ Upstream commit 2ecb7402cfc7f22764e7bbc80790e66eadb20560 ]

kexec reboot fails randomly in UEFI based KVM guest.  The firmware
just resets while calling efi_delete_dummy_variable();  Unfortunately
I don't know how to debug the firmware, it is also possible a potential
problem on real hardware as well although nobody reproduced it.

The intention of the efi_delete_dummy_variable is to trigger garbage collection
when entering virtual mode.  But SetVirtualAddressMap can only run once
for each physical reboot, thus kexec_enter_virtual_mode() is not necessarily
a good place to clean a dummy object.

Drop the efi_delete_dummy_variable so that kexec reboot can work.

Signed-off-by: Dave Young 
Signed-off-by: Ard Biesheuvel 
Acked-by: Matthew Garrett 
Cc: Ben Dooks 
Cc: Jarkko Sakkinen 
Cc: Jerry Snitselaar 
Cc: Linus Torvalds 
Cc: Lukas Wunner 
Cc: Lyude Paul 
Cc: Octavian Purdila 
Cc: Peter Jones 
Cc: Peter Zijlstra 
Cc: Scott Talbert 
Cc: Thomas Gleixner 
Cc: linux-efi@vger.kernel.org
Cc: linux-integrity@vger.kernel.org
Link: https://lkml.kernel.org/r/20191002165904.8819-8-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar 
Signed-off-by: Sasha Levin

Revert "x86/platform/UV: Use efi_runtime_lock to serialise BIOS calls"

2019-03-23T07:44:28+00:00

This reverts commit 7212e37cbdf99f48e4a6c689a42f4bda1ae69001.

Hedi Berriche  notes:

> In 4.4-stable efi_runtime_lock as defined in drivers/firmware/efi/runtime-wrappers.c
> is a spinlock (given it predates commit dce48e351c0d) and commit
>
>         f331e766c4be x86/platform/UV: Use efi_runtime_lock to serialise BIOS calls
>
> which 7212e37cbdf9 is a backport of, needs it to be a semaphore.

Signed-off-by: Sasha Levin

x86/platform/UV: Use efi_runtime_lock to serialise BIOS calls

2019-02-20T09:13:23+00:00

commit f331e766c4be33f4338574f3c9f7f77e98ab4571 upstream.

Calls into UV firmware must be protected against concurrency, expose the
efi_runtime_lock to the UV platform, and use it to serialise UV BIOS
calls.

Signed-off-by: Hedi Berriche 
Signed-off-by: Borislav Petkov 
Reviewed-by: Ard Biesheuvel 
Reviewed-by: Russ Anderson 
Reviewed-by: Dimitri Sivanich 
Reviewed-by: Mike Travis 
Cc: Andy Shevchenko 
Cc: Bhupesh Sharma 
Cc: Darren Hart 
Cc: "H. Peter Anvin" 
Cc: Ingo Molnar 
Cc: linux-efi 
Cc: platform-driver-x86@vger.kernel.org
Cc: stable@vger.kernel.org # v4.9+
Cc: Steve Wahl 
Cc: Thomas Gleixner 
Cc: x86-ml 
Link: https://lkml.kernel.org/r/20190213193413.25560-5-hedi.berriche@hpe.com
Signed-off-by: Greg Kroah-Hartman

x86/earlyprintk/efi: Fix infinite loop on some screen widths

2018-12-21T13:09:52+00:00

[ Upstream commit 79c2206d369b87b19ac29cb47601059b6bf5c291 ]

An affected screen resolution is 1366 x 768, which width is not
divisible by 8, the default font width. On such screens, when longer
lines are earlyprintk'ed, overflow-to-next-line can never trigger,
due to the left-most x-coordinate of the next character always less
than the screen width. Earlyprintk will infinite loop in trying to
print the rest of the string but unable to, due to the line being
full.

This patch makes the trigger consider the right-most x-coordinate,
instead of left-most, as the value to compare against the screen
width threshold.

Signed-off-by: YiFei Zhu 
Signed-off-by: Ard Biesheuvel 
Cc: Andy Lutomirski 
Cc: Arend van Spriel 
Cc: Bhupesh Sharma 
Cc: Borislav Petkov 
Cc: Dave Hansen 
Cc: Eric Snowberg 
Cc: Hans de Goede 
Cc: Joe Perches 
Cc: Jon Hunter 
Cc: Julien Thierry 
Cc: Linus Torvalds 
Cc: Marc Zyngier 
Cc: Matt Fleming 
Cc: Nathan Chancellor 
Cc: Peter Zijlstra 
Cc: Sai Praneeth Prakhya 
Cc: Sedat Dilek 
Cc: Thomas Gleixner 
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20181129171230.18699-12-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar 
Signed-off-by: Sasha Levin

x86/speculation: Use IBRS if available before calling into firmware

2018-07-25T08:18:21+00:00

commit dd84441a797150dcc49298ec95c459a8891d8bb1 upstream.

Retpoline means the kernel is safe because it has no indirect branches.
But firmware isn't, so use IBRS for firmware calls if it's available.

Block preemption while IBRS is set, although in practice the call sites
already had to be doing that.

Ignore hpwdt.c for now. It's taking spinlocks and calling into firmware
code, from an NMI handler. I don't want to touch that with a bargepole.

Signed-off-by: David Woodhouse 
Reviewed-by: Thomas Gleixner 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: arjan.van.de.ven@intel.com
Cc: bp@alien8.de
Cc: dave.hansen@intel.com
Cc: jmattson@google.com
Cc: karahmed@amazon.de
Cc: kvm@vger.kernel.org
Cc: pbonzini@redhat.com
Cc: rkrcmar@redhat.com
Link: http://lkml.kernel.org/r/1519037457-7643-2-git-send-email-dwmw@amazon.co.uk
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman 
[ Srivatsa: Backported to 4.4.y, patching the efi_call_virt() family of functions,
  which are the 4.4.y-equivalents of arch_efi_call_virt_setup()/teardown() ]
Signed-off-by: Srivatsa S. Bhat 
Reviewed-by: Matt Helsley (VMware) 
Reviewed-by: Alexey Makhalov 
Reviewed-by: Bo Gan 
Signed-off-by: Greg Kroah-Hartman

x86/platform/olpc: Fix resume handler build warning

2018-02-25T10:03:47+00:00

commit 20ab6677716c7bbdcfd1cdb9aef296a0b3101f73 upstream.

Fix:

  arch/x86/platform/olpc/olpc-xo15-sci.c:199:12: warning: ‘xo15_sci_resume’
  defined but not used [-Wunused-function]
   static int xo15_sci_resume(struct device *dev)
              ^

which I see in randconfig builds here.

Signed-off-by: Borislav Petkov 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/20161126142706.13602-1-bp@alien8.de
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

Revert "x86/mm/pat: Ensure cpa->pfn only contains page frame numbers"

2017-12-16T09:33:57+00:00

This reverts commit 87e2bd898d3a79a8c609f183180adac47879a2a4 which is
commit edc3b9129cecd0f0857112136f5b8b1bc1d45918 upstream.

Turns there was too many other issues with this patch to make it viable
for the stable tree.

Reported-by: Ben Hutchings 
Cc: Matt Fleming 
Cc: Borislav Petkov 
Cc: Andrew Morton 
Cc: Andy Lutomirski 
Cc: Andy Lutomirski 
Cc: Ard Biesheuvel 
Cc: Borislav Petkov 
Cc: Brian Gerst 
Cc: Dave Jones 
Cc: Denys Vlasenko 
Cc: H. Peter Anvin 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Sai Praneeth Prakhya 
Cc: Stephen Smalley 
Cc: Thomas Gleixner 
Cc: Toshi Kani 
Cc: linux-efi@vger.kernel.org
Cc: Ingo Molnar 
Cc: "Ghannam, Yazen" 
Signed-off-by: Greg Kroah-Hartman

Revert "x86/efi: Hoist page table switching code into efi_call_virt()"

2017-12-16T09:33:57+00:00

This reverts commit b73adb60852034d84092d123b323196ca42529cd which is
commit c9f2a9a65e4855b74d92cdad688f6ee4a1a323ff upstream.

Turns there was too many other issues with this patch to make it viable
for the stable tree.

Reported-by: Ben Hutchings 
Cc: Matt Fleming 
Cc: Borislav Petkov 
Cc: Andrew Morton 
Cc: Andy Lutomirski 
Cc: Andy Lutomirski 
Cc: Ard Biesheuvel 
Cc: Borislav Petkov 
Cc: Brian Gerst 
Cc: Dave Jones 
Cc: Denys Vlasenko 
Cc: H. Peter Anvin 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Sai Praneeth Prakhya 
Cc: Stephen Smalley 
Cc: Thomas Gleixner 
Cc: Toshi Kani 
Cc: linux-efi@vger.kernel.org
Cc: Ingo Molnar 
Cc: "Ghannam, Yazen" 
Signed-off-by: Greg Kroah-Hartman

Revert "x86/efi: Build our own page table structures"

2017-12-16T09:33:57+00:00

This reverts commit 36e0f05afd4e1d09fd47936761a502aedbc50649 which is
commit 67a9108ed4313b85a9c53406d80dc1ae3f8c3e36 upstream.

Turns there was too many other issues with this patch to make it viable
for the stable tree.

Reported-by: Ben Hutchings 
Cc: Matt Fleming 
Cc: Borislav Petkov 
Cc: Andrew Morton 
Cc: Andy Lutomirski 
Cc: Andy Lutomirski 
Cc: Ard Biesheuvel 
Cc: Borislav Petkov 
Cc: Brian Gerst 
Cc: Dave Jones 
Cc: Denys Vlasenko 
Cc: H. Peter Anvin 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Sai Praneeth Prakhya 
Cc: Stephen Smalley 
Cc: Thomas Gleixner 
Cc: Toshi Kani 
Cc: linux-efi@vger.kernel.org
Cc: Ingo Molnar 
Cc: "Ghannam, Yazen" 
Signed-off-by: Greg Kroah-Hartman