summaryrefslogtreecommitdiff
path: root/arch/x86/entry
diff options
context:
space:
mode:
authorAndy Lutomirski <luto@kernel.org>2020-06-26 20:21:13 +0300
committerThomas Gleixner <tglx@linutronix.de>2020-07-01 11:00:26 +0300
commitffae641f57476369b4d503402b37ebe489d23395 (patch)
tree66ad35049b3c31cf7256e2aa29ddbb1a420d2c8d /arch/x86/entry
parentd1721250f3ffed9afba3e1fb729947cec64c5a8a (diff)
downloadlinux-ffae641f57476369b4d503402b37ebe489d23395.tar.xz
x86/entry/64/compat: Fix Xen PV SYSENTER frame setup
The SYSENTER frame setup was nonsense. It worked by accident because the normal code into which the Xen asm jumped (entry_SYSENTER_32/compat) threw away SP without touching the stack. entry_SYSENTER_compat was recently modified such that it relied on having a valid stack pointer, so now the Xen asm needs to invoke it with a valid stack. Fix it up like SYSCALL: use the Xen-provided frame and skip the bare metal prologue. Fixes: 1c3e5d3f60e2 ("x86/entry: Make entry_64_compat.S objtool clean") Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lkml.kernel.org/r/947880c41ade688ff4836f665d0c9fcaa9bd1201.1593191971.git.luto@kernel.org
Diffstat (limited to 'arch/x86/entry')
-rw-r--r--arch/x86/entry/entry_64_compat.S1
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S
index 7b9d8150f652..381a6de7de9c 100644
--- a/arch/x86/entry/entry_64_compat.S
+++ b/arch/x86/entry/entry_64_compat.S
@@ -79,6 +79,7 @@ SYM_CODE_START(entry_SYSENTER_compat)
pushfq /* pt_regs->flags (except IF = 0) */
pushq $__USER32_CS /* pt_regs->cs */
pushq $0 /* pt_regs->ip = 0 (placeholder) */
+SYM_INNER_LABEL(entry_SYSENTER_compat_after_hwframe, SYM_L_GLOBAL)
pushq %rax /* pt_regs->orig_ax */
pushq %rdi /* pt_regs->di */
pushq %rsi /* pt_regs->si */