A bug in kvm caused it to fail on long-mode lidt/lgdt. This patch tests for the failure.
However, kvm doesn't allow lidt/lgdt from mmio, so the test is disabled. Signed-off-by: Avi Kivity <[email protected]> --- x86/emulator.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/x86/emulator.c b/x86/emulator.c index 4867f58..337429c 100644 --- a/x86/emulator.c +++ b/x86/emulator.c @@ -718,6 +718,35 @@ static void test_crosspage_mmio(volatile uint8_t *mem) report("cross-page mmio write", mem[4095] == 0xaa && mem[4096] == 0x88); } +static void test_lgdt_lidt(volatile uint8_t *mem) +{ + struct descriptor_table_ptr orig, fresh = {}; + + sgdt(&orig); + *(struct descriptor_table_ptr *)mem = (struct descriptor_table_ptr) { + .limit = 0xf234, + .base = 0x12345678abcd, + }; + cli(); + asm volatile("lgdt %0" : : "m"(*(struct descriptor_table_ptr *)mem)); + sgdt(&fresh); + lgdt(&orig); + sti(); + report("lgdt (long address)", orig.limit == fresh.limit && orig.base == fresh.base); + + sidt(&orig); + *(struct descriptor_table_ptr *)mem = (struct descriptor_table_ptr) { + .limit = 0x432f, + .base = 0xdbca87654321, + }; + cli(); + asm volatile("lidt %0" : : "m"(*(struct descriptor_table_ptr *)mem)); + sidt(&fresh); + lidt(&orig); + sti(); + report("lidt (long address)", orig.limit == fresh.limit && orig.base == fresh.base); +} + int main() { void *mem; @@ -768,6 +797,7 @@ int main() test_mmx(mem); test_rip_relative(mem, insn_ram); test_shld_shrd(mem); + //test_lgdt_lidt(mem); test_mmx_movq_mf(mem, insn_page, alt_insn_page, insn_ram); -- 1.7.11 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
