linux/arch/x86
Dave Young af16489848 x86/efi: Update e820 with reserved EFI boot services data to fix kexec breakage
Michael Weiser reported that he got this error during a kexec rebooting:

  esrt: Unsupported ESRT version 2904149718861218184.

The ESRT memory stays in EFI boot services data, and it was reserved
in kernel via efi_mem_reserve().  The initial purpose of the reservation
is to reuse the EFI boot services data across kexec reboot. For example
the BGRT image data and some ESRT memory like Michael reported.

But although the memory is reserved it is not updated in the X86 E820 table,
and kexec_file_load() iterates system RAM in the IO resource list to find places
for kernel, initramfs and other stuff. In Michael's case the kexec loaded
initramfs overwrote the ESRT memory and then the failure happened.

Since kexec_file_load() depends on the E820 table being updated, just fix this
by updating the reserved EFI boot services memory as reserved type in E820.

Originally any memory descriptors with EFI_MEMORY_RUNTIME attribute are
bypassed in the reservation code path because they are assumed as reserved.

But the reservation is still needed for multiple kexec reboots,
and it is the only possible case we come here thus just drop the code
chunk, then everything works without side effects.

On my machine the ESRT memory sits in an EFI runtime data range, it does
not trigger the problem, but I successfully tested with BGRT instead.
both kexec_load() and kexec_file_load() work and kdump works as well.

[ mingo: Edited the changelog. ]

Reported-by: Michael Weiser <michael@weiser.dinsnail.net>
Tested-by: Michael Weiser <michael@weiser.dinsnail.net>
Signed-off-by: Dave Young <dyoung@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kexec@lists.infradead.org
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191204075233.GA10520@dhcp-128-65.nay.redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-04 11:15:30 +01:00
..
boot ACPI updates for 5.5-rc1 2019-11-26 19:25:25 -08:00
configs x86: Remove the calgary IOMMU driver 2019-11-15 10:36:59 +01:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2019-12-02 17:23:21 -08:00
entry Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-12-01 19:05:07 -08:00
events perf/x86: Implement immediate enforcement of /sys/devices/cpu/rdpmc value of 0 2019-11-27 10:32:11 +01:00
hyperv - Support for new VMBus protocols (Andrea Parri). 2019-11-30 14:50:51 -08:00
ia32 syscalls/x86: Use COMPAT_SYSCALL_DEFINE0 for IA32 (rt_)sigreturn 2019-10-11 12:49:18 +02:00
include IOMMU Updates for Linux v5.5 2019-12-02 11:05:00 -08:00
kernel Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-12-01 19:05:07 -08:00
kvm Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-11-26 15:42:43 -08:00
lib perf/core improvements and fixes: 2019-11-29 06:56:05 +01:00
math-emu Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-11-26 10:42:40 -08:00
mm Merge branch 'akpm' (patches from Andrew) 2019-12-01 20:36:41 -08:00
net bpf: Simplify __bpf_arch_text_poke poke type handling 2019-11-24 17:12:11 -08:00
oprofile x86: Use pr_warn instead of pr_warning 2019-10-18 15:00:18 +02:00
pci pci-v5.5-changes 2019-12-03 13:58:22 -08:00
platform x86/efi: Update e820 with reserved EFI boot services data to fix kexec breakage 2019-12-04 11:15:30 +01:00
power x86/asm/32: Change all ENTRY+ENDPROC to SYM_FUNC_* 2019-10-18 12:03:43 +02:00
purgatory Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-11-26 10:42:40 -08:00
ras RAS/CEC: Add CONFIG_RAS_CEC_DEBUG and move CEC debug features there 2019-06-08 17:39:24 +02:00
realmode Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-11-26 10:42:40 -08:00
tools x86/insn: Fix awk regexp warnings 2019-10-01 12:13:16 +02:00
um y2038: syscall implementation cleanups 2019-12-01 14:00:59 -08:00
video treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
xen Merge branch 'x86-iopl-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-11-26 11:12:02 -08:00
.gitignore
Kbuild treewide: Add SPDX license identifier - Kbuild 2019-05-30 11:32:33 -07:00
Kconfig x86/kasan: support KASAN_VMALLOC 2019-12-01 12:59:06 -08:00
Kconfig.cpu x86/math-emu: Limit MATH_EMULATION to 486SX compatibles 2019-10-03 10:51:17 +02:00
Kconfig.debug x86/traps: Disentangle the 32-bit and 64-bit doublefault code 2019-11-26 21:53:34 +01:00
Makefile x86/build: Add -Wnoaddress-of-packed-member to REALMODE_CFLAGS, to silence GCC9 build warning 2019-08-28 17:31:31 +02:00
Makefile_32.cpu x86/math-emu: Limit MATH_EMULATION to 486SX compatibles 2019-10-03 10:51:17 +02:00
Makefile.um