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| author |   Thomas Gleixner <tglx@linutronix.de> | 2022-09-15 13:10:40 +0200 |
|---|---|---|
| committer |   Borislav Petkov <bp@suse.de> | 2022-09-21 12:30:16 +0200 |
| commit | f92ff8f5dca2acfa475842c71212657b0703c3be (patch) | |
| tree | eef0269eafb93b7cebb66724d3e4dea26eda930d | |
| parent | Linux 6.0-rc6 (diff) | |
| download | linux-dev-f92ff8f5dca2acfa475842c71212657b0703c3be.tar.xz linux-dev-f92ff8f5dca2acfa475842c71212657b0703c3be.zip | |
x86/paravirt: Ensure proper alignment
The entries in the .parainstructions sections are 8 byte aligned and the
corresponding C struct paravirt_patch_site makes the array offset 16
bytes.
Though the pushed entries are only using 12 bytes, __parainstructions_end
is therefore 4 bytes short.
That works by chance because it's only used in a loop:
for (p = start; p < end; p++)
But this falls flat when calculating the number of elements:
n = end - start
That's obviously off by one.
Ensure that the gap is filled and the last entry is occupying 16 bytes.
[ bp: Add the proper struct and section names. ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20220915111142.992398801@infradead.org
| -rw-r--r-- | arch/x86/include/asm/paravirt.h | 1 | ||||
| -rw-r--r-- | arch/x86/include/asm/paravirt_types.h | 1 |
2 files changed, 2 insertions, 0 deletions
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h index 964442b99245..2a0b8dd4ec33 100644 --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -743,6 +743,7 @@ extern void default_banner(void); word 771b; \ .byte ptype; \ .byte 772b-771b; \ + _ASM_ALIGN; \ .popsection diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h index 89df6c6617f5..27b036a15f70 100644 --- a/arch/x86/include/asm/paravirt_types.h +++ b/arch/x86/include/asm/paravirt_types.h @@ -294,6 +294,7 @@ extern struct paravirt_patch_template pv_ops; " .byte " type "\n" \ " .byte 772b-771b\n" \ " .short " clobber "\n" \ + _ASM_ALIGN "\n" \ ".popsection\n" /* Generate patchable code, with the default asm parameters. */ |