4.18-stable review patch. If anyone has any objections, please let me know.
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From: Ard Biesheuvel ard.biesheuvel@linaro.org
[ Upstream commit 61f0d55569463a1af897117ff47d202b0ccb2e24 ]
The following commit:
7e1550b8f208 ("efi: Drop type and attribute checks in efi_mem_desc_lookup()")
refactored the implementation of efi_mem_desc_lookup() so that the type check is moved to the callers, one of which is the x86 version of efi_arch_mem_reserve(), where we added a modified check that only takes EFI_BOOT_SERVICES_DATA regions into account.
This is reasonable, since it is the only memory type that requires this, but doing so uncovered some unexpected behavior in the ESRT code, which permits the ESRT table to reside in other types of memory than what the UEFI spec mandates (i.e., EFI_BOOT_SERVICES_DATA), and unconditionally calls efi_mem_reserve() on the region in question. This may result in errors such as
esrt: Reserving ESRT space from 0x000000009c810318 to 0x000000009c810350. efi: Failed to lookup EFI memory descriptor for 0x000000009c810318
when the ESRT table is not in EFI_BOOT_SERVICES_DATA memory, but we try to reserve it nonetheless.
So make the call to efi_mem_reserve() conditional on the memory type.
Signed-off-by: Ard Biesheuvel ard.biesheuvel@linaro.org Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Peter Jones pjones@redhat.com Cc: Peter Zijlstra peterz@infradead.org Cc: Thomas Gleixner tglx@linutronix.de Cc: linux-efi@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar mingo@kernel.org Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/firmware/efi/esrt.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/firmware/efi/esrt.c +++ b/drivers/firmware/efi/esrt.c @@ -326,7 +326,8 @@ void __init efi_esrt_init(void)
end = esrt_data + size; pr_info("Reserving ESRT space from %pa to %pa.\n", &esrt_data, &end); - efi_mem_reserve(esrt_data, esrt_data_size); + if (md.type == EFI_BOOT_SERVICES_DATA) + efi_mem_reserve(esrt_data, esrt_data_size);
pr_debug("esrt-init: loaded.\n"); }