On Thu, Sep 24, 2020 at 03:05:17PM +0300, Roman Bolshakov wrote: > clang doesn't properly support .code16gcc and generates wrong machine > code [1][2][3][4]. But the test works if object file is compiled with -m16 and > explicit suffixes are added for instructions. > > 1. https://lore.kernel.org/kvm/4d20fbce-d247-abf4-3ceb-da2c0d48fc50@xxxxxxxxxx/ > 2. https://lore.kernel.org/kvm/20200915155959.GF52559@SPB-NB-133.local/ > 3. https://lore.kernel.org/kvm/788b7191-6987-9399-f352-2e661255157e@xxxxxxxxxx/ > 4. https://lore.kernel.org/kvm/20200922212507.GA11460@SPB-NB-133.local/ > > Suggested-by: Thomas Huth <thuth@xxxxxxxxxx> > Suggested-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> > Signed-off-by: Roman Bolshakov <r.bolshakov@xxxxxxxxx> > --- > .travis.yml | 2 +- > x86/Makefile.common | 2 +- > x86/realmode.c | 44 ++++++++++++++++++++++---------------------- > 3 files changed, 24 insertions(+), 24 deletions(-) > > diff --git a/.travis.yml b/.travis.yml > index 2e5ae41..bd62190 100644 > --- a/.travis.yml > +++ b/.travis.yml > @@ -24,7 +24,7 @@ jobs: > - BUILD_DIR="." > - TESTS="access asyncpf debug emulator ept hypercall hyperv_stimer > hyperv_synic idt_test intel_iommu ioapic ioapic-split > - kvmclock_test msr pcid rdpru rmap_chain s3 setjmp umip" > + kvmclock_test msr pcid rdpru realmode rmap_chain s3 setjmp umip" > - ACCEL="kvm" > > - addons: > diff --git a/x86/Makefile.common b/x86/Makefile.common > index 090ce22..5567d66 100644 > --- a/x86/Makefile.common > +++ b/x86/Makefile.common > @@ -72,7 +72,7 @@ $(TEST_DIR)/realmode.elf: $(TEST_DIR)/realmode.o > $(CC) -m32 -nostdlib -o $@ -Wl,-m,elf_i386 \ > -Wl,-T,$(SRCDIR)/$(TEST_DIR)/realmode.lds $^ > > -$(TEST_DIR)/realmode.o: bits = 32 > +$(TEST_DIR)/realmode.o: bits = 16 > > $(TEST_DIR)/kvmclock_test.elf: $(TEST_DIR)/kvmclock.o > > diff --git a/x86/realmode.c b/x86/realmode.c > index 7c2d776..c8a6ae0 100644 > --- a/x86/realmode.c > +++ b/x86/realmode.c > @@ -639,7 +639,7 @@ static void test_jcc_near(void) > > static void test_long_jmp(void) > { > - MK_INSN(long_jmp, "call 1f\n\t" > + MK_INSN(long_jmp, "calll 1f\n\t" > "jmp 2f\n\t" > "1: jmp $0, $test_function\n\t" > "2:\n\t"); > @@ -728,26 +728,26 @@ static void test_null(void) > > static void test_pusha_popa(void) > { > - MK_INSN(pusha, "pusha\n\t" > - "pop %edi\n\t" > - "pop %esi\n\t" > - "pop %ebp\n\t" > - "add $4, %esp\n\t" > - "pop %ebx\n\t" > - "pop %edx\n\t" > - "pop %ecx\n\t" > - "pop %eax\n\t" > + MK_INSN(pusha, "pushal\n\t" > + "popl %edi\n\t" > + "popl %esi\n\t" > + "popl %ebp\n\t" > + "addl $4, %esp\n\t" > + "popl %ebx\n\t" > + "popl %edx\n\t" > + "popl %ecx\n\t" > + "popl %eax\n\t" > ); > > - MK_INSN(popa, "push %eax\n\t" > - "push %ecx\n\t" > - "push %edx\n\t" > - "push %ebx\n\t" > - "push %esp\n\t" > - "push %ebp\n\t" > - "push %esi\n\t" > - "push %edi\n\t" > - "popa\n\t" > + MK_INSN(popa, "pushl %eax\n\t" > + "pushl %ecx\n\t" > + "pushl %edx\n\t" > + "pushl %ebx\n\t" > + "pushl %esp\n\t" > + "pushl %ebp\n\t" > + "pushl %esi\n\t" > + "pushl %edi\n\t" > + "popal\n\t" > ); > > init_inregs(&(struct regs){ .eax = 0, .ebx = 1, .ecx = 2, .edx = 3, .esi = 4, .edi = 5, .ebp = 6 }); > @@ -761,9 +761,9 @@ static void test_pusha_popa(void) > > static void test_iret(void) > { > - MK_INSN(iret32, "pushf\n\t" > + MK_INSN(iret32, "pushfl\n\t" > "pushl %cs\n\t" > - "call 1f\n\t" /* a near call will push eip onto the stack */ > + "calll 1f\n\t" /* a near call will push eip onto the stack */ > "jmp 2f\n\t" > "1: iretl\n\t" > "2:\n\t" > @@ -782,7 +782,7 @@ static void test_iret(void) > "orl $0xffc18028, %eax\n\t" > "pushl %eax\n\t" > "pushl %cs\n\t" > - "call 1f\n\t" > + "calll 1f\n\t" > "jmp 2f\n\t" > "1: iretl\n\t" > "2:\n\t"); > -- > 2.28.0 > Hi, I've noticed that the patch has been applied (thanks for that!) but a test fails for centos-7. It has gcc that doesn't support "-m16": https://gitlab.com/kvm-unit-tests/kvm-unit-tests/-/jobs/755387059 I'm going to come up with a patch that adds a test for the option and fixes the issue for older gcc, then bits = 16 would be used for modern compilers only. Regards, Roman
