Commit e934c9c1 authored by Avi Kivity's avatar Avi Kivity
Browse files

KVM: x86 emulator: fix eflags preparation for emulation 



We prepare eflags for the emulated instruction, then clobber it with an 'andl'.
Fix by popping eflags as the last thing in the sequence.

Patch taken from Xen (16143:959b4b92b6bf)

Signed-off-by: default avatarAvi Kivity <avi@qumranet.com>
parent 7ee5d940

drivers/kvm/x86_emulate.c

+15 −15
Original line number Diff line number Diff line
@@ -257,20 +257,20 @@ static u16 twobyte_table[256] = { 


/* Before executing instruction: restore necessary bits in EFLAGS. */

#define _PRE_EFLAGS(_sav, _msk, _tmp)					\

	/* EFLAGS = (_sav & _msk) | (EFLAGS & ~_msk); */	\

	"push %"_sav"; "					\

	/* EFLAGS = (_sav & _msk) | (EFLAGS & ~_msk); _sav &= ~_msk; */ \

	"movl %"_sav",%"_LO32 _tmp"; "                                  \

	"push %"_tmp"; "                                                \

	"push %"_tmp"; "                                                \

	"movl %"_msk",%"_LO32 _tmp"; "                                  \

	"andl %"_LO32 _tmp",("_STK"); "                                 \

	"pushf; "                                                       \

	"notl %"_LO32 _tmp"; "                                          \

	"andl %"_LO32 _tmp",("_STK"); "                                 \

	"andl %"_LO32 _tmp","__stringify(BITS_PER_LONG/4)"("_STK"); "	\

	"pop  %"_tmp"; "                                                \

	"orl  %"_LO32 _tmp",("_STK"); "                                 \

	"popf; "                                                        \

	/* _sav &= ~msk; */					\

	"movl %"_msk",%"_LO32 _tmp"; "				\

	"notl %"_LO32 _tmp"; "					\

	"andl %"_LO32 _tmp",%"_sav"; "

	"pop  %"_sav"; "



/* After executing instruction: write-back necessary bits in EFLAGS. */

#define _POST_EFLAGS(_sav, _msk, _tmp) \