On 6/26/20 1:21 PM, Andy Lutomirski wrote: > 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. > > Cc: Boris Ostrovsky <[email protected]> > Cc: Juergen Gross <[email protected]> > Cc: Stefano Stabellini <[email protected]> > Cc: [email protected] > Fixes: 1c3e5d3f60e2 ("x86/entry: Make entry_64_compat.S objtool clean") > Signed-off-by: Andy Lutomirski <[email protected]>
Reviewed-by: Boris Ostrovsky <[email protected]>
