Commit 5d17d4ed authored by Sven Schnelle's avatar Sven Schnelle Committed by Vasily Gorbik
Browse files

s390: introduce nospec_uses_trampoline() 



and replace all of the "__is_defined(CC_USING_EXPOLINE) && !nospec_disable"
occurrences.

Signed-off-by: default avatarSven Schnelle <svens@linux.ibm.com>
Reviewed-by: default avatarHeiko Carstens <hca@linux.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
parent 26c21aa4

arch/s390/include/asm/nospec-branch.h

+5 −0
Original line number Diff line number Diff line
@@ -12,6 +12,11 @@ void nospec_init_branches(void); 
void nospec_auto_detect(void);

void nospec_revert(s32 *start, s32 *end);



static inline bool nospec_uses_trampoline(void)

{

	return __is_defined(CC_USING_EXPOLINE) && !nospec_disable;

}



#endif /* __ASSEMBLY__ */



#endif /* _ASM_S390_EXPOLINE_H */

arch/s390/kernel/nospec-branch.c

+1 −1
Original line number Diff line number Diff line
@@ -38,7 +38,7 @@ static int __init nospec_report(void) 
{

	if (test_facility(156))

		pr_info("Spectre V2 mitigation: etokens\n");

	if (__is_defined(CC_USING_EXPOLINE) && !nospec_disable)

	if (nospec_uses_trampoline())

		pr_info("Spectre V2 mitigation: execute trampolines\n");

	if (__test_facility(82, alt_stfle_fac_list))

		pr_info("Spectre V2 mitigation: limited branch prediction\n");

arch/s390/kernel/nospec-sysfs.c

+1 −1
Original line number Diff line number Diff line
@@ -15,7 +15,7 @@ ssize_t cpu_show_spectre_v2(struct device *dev, 
{

	if (test_facility(156))

		return sprintf(buf, "Mitigation: etokens\n");

	if (__is_defined(CC_USING_EXPOLINE) && !nospec_disable)

	if (nospec_uses_trampoline())

		return sprintf(buf, "Mitigation: execute trampolines\n");

	if (__test_facility(82, alt_stfle_fac_list))

		return sprintf(buf, "Mitigation: limited branch prediction\n");

arch/s390/net/bpf_jit_comp.c

+3 −3
Original line number Diff line number Diff line
@@ -567,7 +567,7 @@ static void bpf_jit_epilogue(struct bpf_jit *jit, u32 stack_depth) 
	EMIT4(0xb9040000, REG_2, BPF_REG_0);

	/* Restore registers */

	save_restore_regs(jit, REGS_RESTORE, stack_depth);

	if (__is_defined(CC_USING_EXPOLINE) && !nospec_disable) {

	if (nospec_uses_trampoline()) {

		jit->r14_thunk_ip = jit->prg;

		/* Generate __s390_indirect_jump_r14 thunk */

		if (test_facility(35)) {
@@ -585,7 +585,7 @@ static void bpf_jit_epilogue(struct bpf_jit *jit, u32 stack_depth) 
	/* br %r14 */

	_EMIT2(0x07fe);



	if (__is_defined(CC_USING_EXPOLINE) && !nospec_disable &&

	if ((nospec_uses_trampoline()) &&

	    (is_first_pass(jit) || (jit->seen & SEEN_FUNC))) {

		jit->r1_thunk_ip = jit->prg;

		/* Generate __s390_indirect_jump_r1 thunk */
@@ -1332,7 +1332,7 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp, 
		jit->seen |= SEEN_FUNC;

		/* lgrl %w1,func */

		EMIT6_PCREL_RILB(0xc4080000, REG_W1, _EMIT_CONST_U64(func));

		if (__is_defined(CC_USING_EXPOLINE) && !nospec_disable) {

		if (nospec_uses_trampoline()) {

			/* brasl %r14,__s390_indirect_jump_r1 */

			EMIT6_PCREL_RILB(0xc0050000, REG_14, jit->r1_thunk_ip);

		} else {