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| author | Josh Poimboeuf <jpoimboe@redhat.com> | 2021-01-21 22:29:29 +0100 |
|---|---|---|
| committer | Josh Poimboeuf <jpoimboe@redhat.com> | 2021-01-26 18:33:02 +0100 |
| commit | f4b4bc10b0b85ec66f1a9bf5dddf475e6695b6d2 (patch) | |
| tree | ffaa44223a525cff4da9616f8583340ae9e75786 /arch/x86/xen/xen-head.S | |
| parent | x86/xen: Support objtool validation in xen-asm.S (diff) | |
| download | linux-f4b4bc10b0b85ec66f1a9bf5dddf475e6695b6d2.tar.xz linux-f4b4bc10b0b85ec66f1a9bf5dddf475e6695b6d2.zip | |
x86/xen: Support objtool vmlinux.o validation in xen-head.S
The Xen hypercall page is filled with zeros, causing objtool to fall
through all the empty hypercall functions until it reaches a real
function, resulting in a stack state mismatch.
The build-time contents of the hypercall page don't matter because the
page gets rewritten by the hypervisor. Make it more palatable to
objtool by making each hypervisor function a true empty function, with
nops and a return.
Cc: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/0883bde1d7a1fb3b6a4c952bc0200e873752f609.1611263462.git.jpoimboe@redhat.com
Diffstat (limited to 'arch/x86/xen/xen-head.S')
| -rw-r--r-- | arch/x86/xen/xen-head.S | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/arch/x86/xen/xen-head.S b/arch/x86/xen/xen-head.S index 2d7c8f34f56c..cb6538ae2fe0 100644 --- a/arch/x86/xen/xen-head.S +++ b/arch/x86/xen/xen-head.S @@ -68,8 +68,9 @@ SYM_CODE_END(asm_cpu_bringup_and_idle) .balign PAGE_SIZE SYM_CODE_START(hypercall_page) .rept (PAGE_SIZE / 32) - UNWIND_HINT_EMPTY - .skip 32 + UNWIND_HINT_FUNC + .skip 31, 0x90 + ret .endr #define HYPERCALL(n) \ |