6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ard Biesheuvel <ardb@xxxxxxxxxx> commit 30c9ca16a5271ba6f8ad9c86507ff1c789c94677 upstream. Make get_sev_encryption_bit() follow the ordinary i386 calling convention, and only call it if CONFIG_AMD_MEM_ENCRYPT is actually enabled. This clarifies the calling code, and makes it more maintainable. Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx> Signed-off-by: Borislav Petkov <bp@xxxxxxx> Link: https://lore.kernel.org/r/20221122161017.2426828-16-ardb@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/x86/boot/compressed/head_64.S | 5 +++-- arch/x86/boot/compressed/mem_encrypt.S | 10 ---------- 2 files changed, 3 insertions(+), 12 deletions(-) --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -180,12 +180,13 @@ SYM_FUNC_START(startup_32) */ /* * If SEV is active then set the encryption mask in the page tables. - * This will insure that when the kernel is copied and decompressed + * This will ensure that when the kernel is copied and decompressed * it will be done so encrypted. */ - call get_sev_encryption_bit xorl %edx, %edx #ifdef CONFIG_AMD_MEM_ENCRYPT + call get_sev_encryption_bit + xorl %edx, %edx testl %eax, %eax jz 1f subl $32, %eax /* Encryption bit is always above bit 31 */ --- a/arch/x86/boot/compressed/mem_encrypt.S +++ b/arch/x86/boot/compressed/mem_encrypt.S @@ -18,12 +18,7 @@ .text .code32 SYM_FUNC_START(get_sev_encryption_bit) - xor %eax, %eax - -#ifdef CONFIG_AMD_MEM_ENCRYPT push %ebx - push %ecx - push %edx movl $0x80000000, %eax /* CPUID to check the highest leaf */ cpuid @@ -54,12 +49,7 @@ SYM_FUNC_START(get_sev_encryption_bit) xor %eax, %eax .Lsev_exit: - pop %edx - pop %ecx pop %ebx - -#endif /* CONFIG_AMD_MEM_ENCRYPT */ - RET SYM_FUNC_END(get_sev_encryption_bit)
