<feed xmlns='http://www.w3.org/2005/Atom'>
<title>talos-op-linux/arch/x86/platform/efi, branch master</title>
<subtitle>Talos™ II Linux sources for OpenPOWER</subtitle>
<id>https://git.raptorcs.com/git/talos-op-linux/atom?h=master</id>
<link rel='self' href='https://git.raptorcs.com/git/talos-op-linux/atom?h=master'/>
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<updated>2020-02-09T19:54:50+00:00</updated>
<entry>
<title>Merge tag 'efi-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2020-02-09T19:54:50+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-02-09T19:54:50+00:00</published>
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<id>urn:sha1:6ff90aa2cfddb1bce5450cb711069315ad17bd14</id>
<content type='text'>
Pull EFI fix from Thomas Gleixner:
 "A single fix for a EFI boot regression on X86 which was caused by the
  recent rework of the EFI memory map parsing. On systems with invalid
  memmap entries the cleanup function uses an value which cannot be
  relied on in this stage. Use the actual EFI memmap entry instead"

* tag 'efi-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/x86: Fix boot regression on systems with invalid memmap entries
</content>
</entry>
<entry>
<title>x86: mm+efi: convert ptdump_walk_pgd_level() to take a mm_struct</title>
<updated>2020-02-04T03:05:25+00:00</updated>
<author>
<name>Steven Price</name>
<email>steven.price@arm.com</email>
</author>
<published>2020-02-04T01:36:11+00:00</published>
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<id>urn:sha1:e455248d5ee9c8a12469d21cfa92c8432be4a4fd</id>
<content type='text'>
To enable x86 to use the generic walk_page_range() function, the callers
of ptdump_walk_pgd_level() need to pass an mm_struct rather than the raw
pgd_t pointer.  Luckily since commit 7e904a91bf60 ("efi: Use efi_mm in x86
as well as ARM") we now have an mm_struct for EFI on x86.

Link: http://lkml.kernel.org/r/20191218162402.45610-18-steven.price@arm.com
Signed-off-by: Steven Price &lt;steven.price@arm.com&gt;
Cc: Albert Ou &lt;aou@eecs.berkeley.edu&gt;
Cc: Alexandre Ghiti &lt;alex@ghiti.fr&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: James Hogan &lt;jhogan@kernel.org&gt;
Cc: James Morse &lt;james.morse@arm.com&gt;
Cc: Jerome Glisse &lt;jglisse@redhat.com&gt;
Cc: "Liang, Kan" &lt;kan.liang@linux.intel.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Paul Burton &lt;paul.burton@mips.com&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Cc: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Cc: Zong Li &lt;zong.li@sifive.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>efi/x86: Fix boot regression on systems with invalid memmap entries</title>
<updated>2020-02-02T09:25:43+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ardb@kernel.org</email>
</author>
<published>2020-02-01T23:33:04+00:00</published>
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<id>urn:sha1:59365cadfbcd299b8cdbe0c165faf15767c5f166</id>
<content type='text'>
In efi_clean_memmap(), we do a pass over the EFI memory map to remove
bogus entries that may be returned on certain systems.

This recent commit:

  1db91035d01aa8bf ("efi: Add tracking for dynamically allocated memmaps")

refactored this code to pass the input to efi_memmap_install() via a
temporary struct on the stack, which is populated using an initializer
which inadvertently defines the value of its size field in terms of its
desc_size field, which value cannot be relied upon yet in the initializer
itself.

Fix this by using efi.memmap.desc_size instead, which is where we get
the value for desc_size from in the first place.

Reported-by: Jörg Otte &lt;jrg.otte@gmail.com&gt;
Tested-by: Jörg Otte &lt;jrg.otte@gmail.com&gt;
Tested-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: linux-efi@vger.kernel.org
Cc: jrg.otte@gmail.com
Cc: torvalds@linux-foundation.org
Cc: mingo@kernel.org
Link: https://lore.kernel.org/r/20200201233304.18322-1-ardb@kernel.org
</content>
</entry>
<entry>
<title>Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2020-01-28T17:03:40+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-01-28T17:03:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.raptorcs.com/git/talos-op-linux/commit/?id=634cd4b6afe15dca8df02bcba242b9b0c5e9b5a5'/>
<id>urn:sha1:634cd4b6afe15dca8df02bcba242b9b0c5e9b5a5</id>
<content type='text'>
Pull EFI updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Cleanup of the GOP [graphics output] handling code in the EFI stub

   - Complete refactoring of the mixed mode handling in the x86 EFI stub

   - Overhaul of the x86 EFI boot/runtime code

   - Increase robustness for mixed mode code

   - Add the ability to disable DMA at the root port level in the EFI
     stub

   - Get rid of RWX mappings in the EFI memory map and page tables,
     where possible

   - Move the support code for the old EFI memory mapping style into its
     only user, the SGI UV1+ support code.

   - plus misc fixes, updates, smaller cleanups.

  ... and due to interactions with the RWX changes, another round of PAT
  cleanups make a guest appearance via the EFI tree - with no side
  effects intended"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (75 commits)
  efi/x86: Disable instrumentation in the EFI runtime handling code
  efi/libstub/x86: Fix EFI server boot failure
  efi/x86: Disallow efi=old_map in mixed mode
  x86/boot/compressed: Relax sed symbol type regex for LLVM ld.lld
  efi/x86: avoid KASAN false positives when accessing the 1: 1 mapping
  efi: Fix handling of multiple efi_fake_mem= entries
  efi: Fix efi_memmap_alloc() leaks
  efi: Add tracking for dynamically allocated memmaps
  efi: Add a flags parameter to efi_memory_map
  efi: Fix comment for efi_mem_type() wrt absent physical addresses
  efi/arm: Defer probe of PCIe backed efifb on DT systems
  efi/x86: Limit EFI old memory map to SGI UV machines
  efi/x86: Avoid RWX mappings for all of DRAM
  efi/x86: Don't map the entire kernel text RW for mixed mode
  x86/mm: Fix NX bit clearing issue in kernel_map_pages_in_pgd
  efi/libstub/x86: Fix unused-variable warning
  efi/libstub/x86: Use mandatory 16-byte stack alignment in mixed mode
  efi/libstub/x86: Use const attribute for efi_is_64bit()
  efi: Allow disabling PCI busmastering on bridges during boot
  efi/x86: Allow translating 64-bit arguments for mixed mode calls
  ...
</content>
</entry>
<entry>
<title>Merge branch 'core-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2020-01-28T16:20:54+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-01-28T16:20:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.raptorcs.com/git/talos-op-linux/commit/?id=9f2a43019edc097347900daade277571834a3e2c'/>
<id>urn:sha1:9f2a43019edc097347900daade277571834a3e2c</id>
<content type='text'>
Pull header cleanup from Ingo Molnar:
 "This is a treewide cleanup, mostly (but not exclusively) with x86
  impact, which breaks implicit dependencies on the asm/realtime.h
  header and finally removes it from asm/acpi.h"

* 'core-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/ACPI/sleep: Move acpi_get_wakeup_address() into sleep.c, remove &lt;asm/realmode.h&gt; from &lt;asm/acpi.h&gt;
  ACPI/sleep: Convert acpi_wakeup_address into a function
  x86/ACPI/sleep: Remove an unnecessary include of asm/realmode.h
  ASoC: Intel: Skylake: Explicitly include linux/io.h for virt_to_phys()
  vmw_balloon: Explicitly include linux/io.h for virt_to_phys()
  virt: vbox: Explicitly include linux/io.h to pick up various defs
  efi/capsule-loader: Explicitly include linux/io.h for page_to_phys()
  perf/x86/intel: Explicitly include asm/io.h to use virt_to_phys()
  x86/kprobes: Explicitly include vmalloc.h for set_vm_flush_reset_perms()
  x86/ftrace: Explicitly include vmalloc.h for set_vm_flush_reset_perms()
  x86/boot: Explicitly include realmode.h to handle RM reservations
  x86/efi: Explicitly include realmode.h to handle RM trampoline quirk
  x86/platform/intel/quark: Explicitly include linux/io.h for virt_to_phys()
  x86/setup: Enhance the comments
  x86/setup: Clean up the header portion of setup.c
</content>
</entry>
<entry>
<title>efi/x86: Disable instrumentation in the EFI runtime handling code</title>
<updated>2020-01-25T09:14:37+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ardb@kernel.org</email>
</author>
<published>2020-01-21T09:39:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.raptorcs.com/git/talos-op-linux/commit/?id=ac6119e7f25b842fc061e8aec88c4f32d3bc28ef'/>
<id>urn:sha1:ac6119e7f25b842fc061e8aec88c4f32d3bc28ef</id>
<content type='text'>
We already disable KASAN instrumentation specifically for the
EFI routines that are known to dereference memory addresses that
KASAN does not know about, avoiding false positive KASAN splats.

However, as it turns out, having GCOV or KASAN instrumentation enabled
interferes with the compiler's ability to optimize away function calls
that are guarded by IS_ENABLED() checks that should have resulted in
those references to have been const-propagated out of existence. But
with instrumenation enabled, we may get build errors like:

   ld: arch/x86/platform/efi/efi_64.o: in function `efi_thunk_set_virtual_address_map':
   ld: arch/x86/platform/efi/efi_64.o: in function `efi_set_virtual_address_map':

in builds where CONFIG_EFI=y but CONFIG_EFI_MIXED or CONFIG_X86_UV are not
defined, even though the invocations are conditional on IS_ENABLED() checks
against the respective Kconfig symbols.

So let's disable instrumentation entirely for this subdirectory, which
isn't that useful here to begin with.

Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: linux-efi@vger.kernel.org
</content>
</entry>
<entry>
<title>efi/x86: avoid KASAN false positives when accessing the 1: 1 mapping</title>
<updated>2020-01-20T07:14:29+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ardb@kernel.org</email>
</author>
<published>2020-01-18T16:57:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.raptorcs.com/git/talos-op-linux/commit/?id=3cc028619e284188cdde652631e1c3c5a83692b9'/>
<id>urn:sha1:3cc028619e284188cdde652631e1c3c5a83692b9</id>
<content type='text'>
When installing the EFI virtual address map during early boot, we
access the EFI system table to retrieve the 1:1 mapped address of
the SetVirtualAddressMap() EFI runtime service. This memory is not
known to KASAN, so on KASAN enabled builds, this may result in a
splat like

  ==================================================================
  BUG: KASAN: user-memory-access in efi_set_virtual_address_map+0x141/0x354
  Read of size 4 at addr 000000003fbeef38 by task swapper/0/0

  CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.5.0-rc5+ #758
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
  Call Trace:
   dump_stack+0x8b/0xbb
   ? efi_set_virtual_address_map+0x141/0x354
   ? efi_set_virtual_address_map+0x141/0x354
   __kasan_report+0x176/0x192
   ? efi_set_virtual_address_map+0x141/0x354
   kasan_report+0xe/0x20
   efi_set_virtual_address_map+0x141/0x354
   ? efi_thunk_runtime_setup+0x148/0x148
   ? __inc_numa_state+0x19/0x90
   ? memcpy+0x34/0x50
   efi_enter_virtual_mode+0x5fd/0x67d
   start_kernel+0x5cd/0x682
   ? mem_encrypt_init+0x6/0x6
   ? x86_family+0x5/0x20
   ? load_ucode_bsp+0x46/0x154
   secondary_startup_64+0xa4/0xb0
  ==================================================================

Since this code runs only a single time during early boot, let's annotate
it as __no_sanitize_address so KASAN disregards it entirely.

Fixes: 698294704573 ("efi/x86: Split SetVirtualAddresMap() wrappers into ...")
Reported-by: Qian Cai &lt;cai@lca.pw&gt;
Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
</entry>
<entry>
<title>efi: Add tracking for dynamically allocated memmaps</title>
<updated>2020-01-20T07:14:29+00:00</updated>
<author>
<name>Dan Williams</name>
<email>dan.j.williams@intel.com</email>
</author>
<published>2020-01-13T17:22:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.raptorcs.com/git/talos-op-linux/commit/?id=1db91035d01aa8bfa2350c00ccb63d629b4041ad'/>
<id>urn:sha1:1db91035d01aa8bfa2350c00ccb63d629b4041ad</id>
<content type='text'>
In preparation for fixing efi_memmap_alloc() leaks, add support for
recording whether the memmap was dynamically allocated from slab,
memblock, or is the original physical memmap provided by the platform.

Given this tracking is established in efi_memmap_alloc() and needs to be
carried to efi_memmap_install(), use 'struct efi_memory_map_data' to
convey the flags.

Some small cleanups result from this reorganization, specifically the
removal of local variables for 'phys' and 'size' that are already
tracked in @data.

Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Link: https://lore.kernel.org/r/20200113172245.27925-12-ardb@kernel.org
</content>
</entry>
<entry>
<title>efi/x86: Limit EFI old memory map to SGI UV machines</title>
<updated>2020-01-20T07:13:01+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ardb@kernel.org</email>
</author>
<published>2020-01-13T17:22:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.raptorcs.com/git/talos-op-linux/commit/?id=1f299fad1e312947c974c6a1d8a3a484f27a6111'/>
<id>urn:sha1:1f299fad1e312947c974c6a1d8a3a484f27a6111</id>
<content type='text'>
We carry a quirk in the x86 EFI code to switch back to an older
method of mapping the EFI runtime services memory regions, because
it was deemed risky at the time to implement a new method without
providing a fallback to the old method in case problems arose.

Such problems did arise, but they appear to be limited to SGI UV1
machines, and so these are the only ones for which the fallback gets
enabled automatically (via a DMI quirk). The fallback can be enabled
manually as well, by passing efi=old_map, but there is very little
evidence that suggests that this is something that is being relied
upon in the field.

Given that UV1 support is not enabled by default by the distros
(Ubuntu, Fedora), there is no point in carrying this fallback code
all the time if there are no other users. So let's move it into the
UV support code, and document that efi=old_map now requires this
support code to be enabled.

Note that efi=old_map has been used in the past on other SGI UV
machines to work around kernel regressions in production, so we
keep the option to enable it by hand, but only if the kernel was
built with UV support.

Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Link: https://lore.kernel.org/r/20200113172245.27925-8-ardb@kernel.org
</content>
</entry>
<entry>
<title>efi/x86: Avoid RWX mappings for all of DRAM</title>
<updated>2020-01-20T07:13:01+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ardb@kernel.org</email>
</author>
<published>2020-01-13T17:22:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.raptorcs.com/git/talos-op-linux/commit/?id=97bb9cdc32108036170d9d0d208257168f80d9e9'/>
<id>urn:sha1:97bb9cdc32108036170d9d0d208257168f80d9e9</id>
<content type='text'>
The EFI code creates RWX mappings for all memory regions that are
occupied after the stub completes, and in the mixed mode case, it
even creates RWX mappings for all of the remaining DRAM as well.

Let's try to avoid this, by setting the NX bit for all memory
regions except the ones that are marked as EFI runtime services
code [which means text+rodata+data in practice, so we cannot mark
them read-only right away]. For cases of buggy firmware where boot
services code is called during SetVirtualAddressMap(), map those
regions with exec permissions as well - they will be unmapped in
efi_free_boot_services().

Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Link: https://lore.kernel.org/r/20200113172245.27925-7-ardb@kernel.org
</content>
</entry>
</feed>
