On Tue, Apr 09, 2024 at 02:29:57PM +0300, Kirill A. Shutemov wrote:
> +1:
> +     testq   $X86_CR4_MCE, %r13
> +     jz      1f
> +     ALTERNATIVE "", __stringify(orl $X86_CR4_MCE, %eax), 
> X86_FEATURE_TDX_GUEST
>  1:

Please add the below patch to your set. Those same-number labels are
just abominable.

Thx.

---
From: "Borislav Petkov (AMD)" <b...@alien8.de>
Date: Tue, 30 Apr 2024 15:00:16 +0200
Subject: [PATCH] x86/relocate_kernel: Use named labels for less confusion

That identity_mapped() function was loving that "1" label to the point
of completely confusing its readers.

Use named labels in each place for clarity.

No functional changes.

Signed-off-by: Borislav Petkov (AMD) <b...@alien8.de>
---
 arch/x86/kernel/relocate_kernel_64.S | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kernel/relocate_kernel_64.S 
b/arch/x86/kernel/relocate_kernel_64.S
index 8e2037d78a1f..0077c9e562a7 100644
--- a/arch/x86/kernel/relocate_kernel_64.S
+++ b/arch/x86/kernel/relocate_kernel_64.S
@@ -152,13 +152,15 @@ SYM_CODE_START_LOCAL_NOALIGN(identity_mapped)
         */
        movl    $X86_CR4_PAE, %eax
        testq   $X86_CR4_LA57, %r13
-       jz      1f
+       jz      no_la57
        orl     $X86_CR4_LA57, %eax
-1:
+no_la57:
+
        testq   $X86_CR4_MCE, %r13
-       jz      1f
+       jz      mca_off
        ALTERNATIVE "", __stringify(orl $X86_CR4_MCE, %eax), 
X86_FEATURE_TDX_GUEST
-1:
+mca_off:
+
        movq    %rax, %cr4
 
        jmp 1f
@@ -173,9 +175,9 @@ SYM_CODE_START_LOCAL_NOALIGN(identity_mapped)
         * used by kexec. Flush the caches before copying the kernel.
         */
        testq   %r12, %r12
-       jz 1f
+       jz sme_off
        wbinvd
-1:
+sme_off:
 
        movq    %rcx, %r11
        call    swap_pages
@@ -195,7 +197,7 @@ SYM_CODE_START_LOCAL_NOALIGN(identity_mapped)
         */
 
        testq   %r11, %r11
-       jnz 1f
+       jnz relocate
        xorl    %eax, %eax
        xorl    %ebx, %ebx
        xorl    %ecx, %ecx
@@ -216,7 +218,7 @@ SYM_CODE_START_LOCAL_NOALIGN(identity_mapped)
        ret
        int3
 
-1:
+relocate:
        popq    %rdx
        leaq    PAGE_SIZE(%r10), %rsp
        ANNOTATE_RETPOLINE_SAFE
-- 
2.43.0

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

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