6.5-stable review patch. If anyone has any objections, please let me know.
------------------
From: Josh Poimboeuf jpoimboe@kernel.org
[ Upstream commit eeb9f34df065f42f0c9195b322ba6df420c9fc92 ]
CONFIG_CPU_SRSO isn't dependent on CONFIG_CPU_UNRET_ENTRY (AMD Retbleed), so the two features are independently configurable. Fix several issues for the (presumably rare) case where CONFIG_CPU_SRSO is enabled but CONFIG_CPU_UNRET_ENTRY isn't.
Fixes: fb3bd914b3ec ("x86/srso: Add a Speculative RAS Overflow mitigation") Signed-off-by: Josh Poimboeuf jpoimboe@kernel.org Signed-off-by: Ingo Molnar mingo@kernel.org Signed-off-by: Borislav Petkov (AMD) bp@alien8.de Acked-by: Borislav Petkov (AMD) bp@alien8.de Link: https://lore.kernel.org/r/299fb7740174d0f2335e91c58af0e9c242b4bac1.169388998... Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/include/asm/nospec-branch.h | 4 ++-- include/linux/objtool.h | 3 ++- scripts/Makefile.vmlinux_o | 3 ++- 3 files changed, 6 insertions(+), 4 deletions(-)
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h index c55cc243592e9..197ff4f4d1ceb 100644 --- a/arch/x86/include/asm/nospec-branch.h +++ b/arch/x86/include/asm/nospec-branch.h @@ -271,7 +271,7 @@ .Lskip_rsb_@: .endm
-#ifdef CONFIG_CPU_UNRET_ENTRY +#if defined(CONFIG_CPU_UNRET_ENTRY) || defined(CONFIG_CPU_SRSO) #define CALL_UNTRAIN_RET "call entry_untrain_ret" #else #define CALL_UNTRAIN_RET "" @@ -312,7 +312,7 @@
.macro UNTRAIN_RET_FROM_CALL #if defined(CONFIG_CPU_UNRET_ENTRY) || defined(CONFIG_CPU_IBPB_ENTRY) || \ - defined(CONFIG_CALL_DEPTH_TRACKING) + defined(CONFIG_CALL_DEPTH_TRACKING) || defined(CONFIG_CPU_SRSO) VALIDATE_UNRET_END ALTERNATIVE_3 "", \ CALL_UNTRAIN_RET, X86_FEATURE_UNRET, \ diff --git a/include/linux/objtool.h b/include/linux/objtool.h index 03f82c2c2ebf6..b5440e7da55bf 100644 --- a/include/linux/objtool.h +++ b/include/linux/objtool.h @@ -130,7 +130,8 @@ * it will be ignored. */ .macro VALIDATE_UNRET_BEGIN -#if defined(CONFIG_NOINSTR_VALIDATION) && defined(CONFIG_CPU_UNRET_ENTRY) +#if defined(CONFIG_NOINSTR_VALIDATION) && \ + (defined(CONFIG_CPU_UNRET_ENTRY) || defined(CONFIG_CPU_SRSO)) .Lhere_@: .pushsection .discard.validate_unret .long .Lhere_@ - . diff --git a/scripts/Makefile.vmlinux_o b/scripts/Makefile.vmlinux_o index 0edfdb40364b8..25b3b587d37c0 100644 --- a/scripts/Makefile.vmlinux_o +++ b/scripts/Makefile.vmlinux_o @@ -37,7 +37,8 @@ objtool-enabled := $(or $(delay-objtool),$(CONFIG_NOINSTR_VALIDATION))
vmlinux-objtool-args-$(delay-objtool) += $(objtool-args-y) vmlinux-objtool-args-$(CONFIG_GCOV_KERNEL) += --no-unreachable -vmlinux-objtool-args-$(CONFIG_NOINSTR_VALIDATION) += --noinstr $(if $(CONFIG_CPU_UNRET_ENTRY), --unret) +vmlinux-objtool-args-$(CONFIG_NOINSTR_VALIDATION) += --noinstr \ + $(if $(or $(CONFIG_CPU_UNRET_ENTRY),$(CONFIG_CPU_SRSO)), --unret)
objtool-args = $(vmlinux-objtool-args-y) --link