Commit 2ab9c93d authored by John Hubbard's avatar John Hubbard Committed by Shuah Khan
Browse files

selftests/x86: build sysret_rip.c with clang 



When building with clang, via:

    make LLVM=1 -C tools/testing/selftests

...the build fails because clang's inline asm doesn't support all of the
features that are used in the asm() snippet in sysret_rip.c.

Fix this by moving the asm code into the clang_helpers_64.S file, where
it can be built with the assembler's full set of features.

Acked-by: default avatarMuhammad Usama Anjum <usama.anjum@collabora.com>
Signed-off-by: default avatarJohn Hubbard <jhubbard@nvidia.com>
Signed-off-by: default avatarShuah Khan <skhan@linuxfoundation.org>
parent 11586553

tools/testing/selftests/x86/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -115,6 +115,7 @@ $(eval $(call extra-files,ptrace_syscall_32,raw_syscall_helper_32.S)) 
$(eval $(call extra-files,test_syscall_vdso_32,thunks_32.S))

$(eval $(call extra-files,fsgsbase_restore_64,clang_helpers_64.S))

$(eval $(call extra-files,fsgsbase_restore_32,clang_helpers_32.S))

$(eval $(call extra-files,sysret_rip_64,clang_helpers_64.S))



# check_initial_reg_state is special: it needs a custom entry, and it

# needs to be static so that its interpreter doesn't destroy its initial

tools/testing/selftests/x86/clang_helpers_64.S

+16 −0
Original line number Diff line number Diff line
@@ -9,4 +9,20 @@ dereference_seg_base: 
	mov %gs:(0), %rax

	ret



.global test_page

.global test_syscall_insn



.pushsection ".text", "ax"

.balign 4096

test_page: .globl test_page

	.fill 4094,1,0xcc



test_syscall_insn:

	syscall



.ifne . - test_page - 4096

	.error "test page is not one page long"

.endif

.popsection



.section .note.GNU-stack,"",%progbits

tools/testing/selftests/x86/sysret_rip.c

+6 −14
Original line number Diff line number Diff line
@@ -22,21 +22,13 @@ 
#include <sys/mman.h>

#include <assert.h>





asm (

	".pushsection \".text\", \"ax\"\n\t"

	".balign 4096\n\t"

	"test_page: .globl test_page\n\t"

	".fill 4094,1,0xcc\n\t"

	"test_syscall_insn:\n\t"

	"syscall\n\t"

	".ifne . - test_page - 4096\n\t"

	".error \"test page is not one page long\"\n\t"

	".endif\n\t"

	".popsection"

    );



/*

 * These items are in clang_helpers_64.S, in order to avoid clang inline asm

 * limitations:

 */

void test_syscall_ins(void);

extern const char test_page[];



static void const *current_test_page_addr = test_page;



static void sethandler(int sig, void (*handler)(int, siginfo_t *, void *),