Re: [PATCHv11 05/19] x86/relocate_kernel: Use named labels for less confusion

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 5/29/24 03:47, Nikolay Borisov wrote:

diff --git a/arch/x86/kernel/relocate_kernel_64.S b/arch/x86/kernel/relocate_kernel_64.S
index 56cab1bb25f5..085eef5c3904 100644
--- a/arch/x86/kernel/relocate_kernel_64.S
+++ b/arch/x86/kernel/relocate_kernel_64.S
@@ -148,9 +148,10 @@ SYM_CODE_START_LOCAL_NOALIGN(identity_mapped)
       */
      movl    $X86_CR4_PAE, %eax
      testq    $X86_CR4_LA57, %r13
-    jz    1f
+    jz    .Lno_la57
      orl    $X86_CR4_LA57, %eax
-1:
+.Lno_la57:
+
      movq    %rax, %cr4
      jmp 1f

That jmp 1f becomes redundant now as it simply jumps 1 line below.


Uh... am I the only person to notice that ALL that is needed here is:

	andl $(X86_CR4_PAE|X86_CR4_LA57), %r13d
	movq %r13, %rax

... since %r13 is dead afterwards, and PAE *will* have been set in %r13 already?

I don't believe that this specific jmp is actually needed -- there are several more synchronizing jumps later -- but it doesn't hurt.

However, if the effort is for improving the readability, it might be worthwhile to encapsulate the "jmp 1f; 1:" as a macro, e.g. "SYNC_CODE".

	-hpa

_______________________________________________
kexec mailing list
kexec@xxxxxxxxxxxxxxxxxxx
http://lists.infradead.org/mailman/listinfo/kexec




[Index of Archives]     [LM Sensors]     [Linux Sound]     [ALSA Users]     [ALSA Devel]     [Linux Audio Users]     [Linux Media]     [Kernel]     [Gimp]     [Yosemite News]     [Linux Media]

  Powered by Linux