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| author | Andy Lutomirski <luto@kernel.org> | 2021-01-21 08:09:50 +0300 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2021-01-29 14:22:15 +0300 |
| commit | b0dc553cfc9d3bc2c7b8672b0b2fcf0edf0c3b6e (patch) | |
| tree | 96c4bd6d9fe44564243e63867c4c0c7e7767141e /arch/x86/platform | |
| parent | 6ee1d745b7c9fd573fba142a2efdad76a9f1cb04 (diff) | |
| download | linux-b0dc553cfc9d3bc2c7b8672b0b2fcf0edf0c3b6e.tar.xz | |
x86/fpu: Make the EFI FPU calling convention explicit
EFI uses kernel_fpu_begin() to conform to the UEFI calling convention.
This specifically requires initializing FCW (FPU Control Word), whereas
no sane 64-bit kernel code should use legacy 387 operations that
reference FCW.
This should allow to safely change the default semantics of
kernel_fpu_begin() to stop initializing FCW on 64-bit kernels.
[ bp: Massage commit message a little. ]
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/25d392fff64680e0f4bb8cf0b1003314dc29eafe.1611205691.git.luto@kernel.org
Diffstat (limited to 'arch/x86/platform')
| -rw-r--r-- | arch/x86/platform/efi/efi_64.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index e1e8d4e3a213..cf7b3bfe1a1e 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -850,7 +850,7 @@ efi_set_virtual_address_map(unsigned long memory_map_size, virtual_map); efi_switch_mm(&efi_mm); - kernel_fpu_begin(); + efi_fpu_begin(); /* Disable interrupts around EFI calls: */ local_irq_save(flags); @@ -859,7 +859,7 @@ efi_set_virtual_address_map(unsigned long memory_map_size, descriptor_version, virtual_map); local_irq_restore(flags); - kernel_fpu_end(); + efi_fpu_end(); /* grab the virtually remapped EFI runtime services table pointer */ efi.runtime = READ_ONCE(systab->runtime); |