On 05/03/2024 2:04 pm, Jan Beulich wrote: > --- a/xen/arch/x86/x86_64/entry.S > +++ b/xen/arch/x86/x86_64/entry.S > @@ -52,7 +52,7 @@ UNLIKELY_END(syscall_no_callback) > movq %rax,TRAPBOUNCE_eip(%rdx) > movb %cl,TRAPBOUNCE_flags(%rdx) > call create_bounce_frame > - andl $~X86_EFLAGS_DF,UREGS_eflags(%rsp) > + andb $~(X86_EFLAGS_DF >> 8), UREGS_eflags + 1(%rsp)
The other adjustments are fine, but what on earth are we doing with DF here? This looks straight up buggy. We've got no legitimate reason to be playing with the guest's view of DF. ~Andrew
