2023-04-28 18:53:01

by Nick Desaulniers

Subject: [PATCH v2] arm64: kernel: remove SHF_WRITE|SHF_EXECINSTR from .idmap.text

commit d54170812ef1 ("arm64: fix .idmap.text assertion for large kernels")
modified some of the section assembler directives that declare
.idmap.text to be SHF_ALLOC instead of
SHF_ALLOC|SHF_WRITE|SHF_EXECINSTR.

This patch fixes up the remaining stragglers that were left behind. Add
Fixes tag so that this doesn't precede related change in stable.

Fixes: d54170812ef1 ("arm64: fix .idmap.text assertion for large kernels")
Reported-by: Greg Thelen <[email protected]>
Reviewed-by: Ard Biesheuvel <[email protected]>
Signed-off-by: Nick Desaulniers <[email protected]>
---
Changes in v2:
- Drop irrelevant paragraph.
- Pick up Ard's RB tag.
- Link to v1: https://lore.kernel.org/r/[email protected]
---
arch/arm64/kernel/cpu-reset.S | 2 +-
arch/arm64/kernel/sleep.S | 2 +-
arch/arm64/mm/proc.S | 6 +++---
3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/kernel/cpu-reset.S b/arch/arm64/kernel/cpu-reset.S
index 6b752fe89745..c87445dde674 100644
--- a/arch/arm64/kernel/cpu-reset.S
+++ b/arch/arm64/kernel/cpu-reset.S
@@ -14,7 +14,7 @@
#include <asm/virt.h>

.text
-.pushsection .idmap.text, "awx"
+.pushsection .idmap.text, "a"

/*
* cpu_soft_restart(el2_switch, entry, arg0, arg1, arg2)
diff --git a/arch/arm64/kernel/sleep.S b/arch/arm64/kernel/sleep.S
index 2ae7cff1953a..2aa5129d8253 100644
--- a/arch/arm64/kernel/sleep.S
+++ b/arch/arm64/kernel/sleep.S
@@ -97,7 +97,7 @@ SYM_FUNC_START(__cpu_suspend_enter)
ret
SYM_FUNC_END(__cpu_suspend_enter)

- .pushsection ".idmap.text", "awx"
+ .pushsection ".idmap.text", "a"
SYM_CODE_START(cpu_resume)
mov x0, xzr
bl init_kernel_el
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
index 91410f488090..c2cb437821ca 100644
--- a/arch/arm64/mm/proc.S
+++ b/arch/arm64/mm/proc.S
@@ -167,7 +167,7 @@ alternative_else_nop_endif
SYM_FUNC_END(cpu_do_resume)
#endif

- .pushsection ".idmap.text", "awx"
+ .pushsection ".idmap.text", "a"

.macro __idmap_cpu_set_reserved_ttbr1, tmp1, tmp2
adrp \tmp1, reserved_pg_dir
@@ -201,7 +201,7 @@ SYM_FUNC_END(idmap_cpu_replace_ttbr1)

#define KPTI_NG_PTE_FLAGS (PTE_ATTRINDX(MT_NORMAL) | SWAPPER_PTE_FLAGS)

- .pushsection ".idmap.text", "awx"
+ .pushsection ".idmap.text", "a"

.macro kpti_mk_tbl_ng, type, num_entries
add end_\type\()p, cur_\type\()p, #\num_entries * 8
@@ -400,7 +400,7 @@ SYM_FUNC_END(idmap_kpti_install_ng_mappings)
* Output:
* Return in x0 the value of the SCTLR_EL1 register.
*/
- .pushsection ".idmap.text", "awx"
+ .pushsection ".idmap.text", "a"
SYM_FUNC_START(__cpu_setup)
tlbi vmalle1 // Invalidate local TLB
dsb nsh

---
base-commit: 22b8cc3e78f5448b4c5df00303817a9137cd663f
change-id: 20230428-awx-c73f4bde79c4

Best regards,
--
Nick Desaulniers <[email protected]>

2023-05-02 12:16:16

by Will Deacon

Subject: Re: [PATCH v2] arm64: kernel: remove SHF_WRITE|SHF_EXECINSTR from .idmap.text

On Fri, 28 Apr 2023 11:28:17 -0700, [email protected] wrote:
> commit d54170812ef1 ("arm64: fix .idmap.text assertion for large kernels")
> modified some of the section assembler directives that declare
> .idmap.text to be SHF_ALLOC instead of
> SHF_ALLOC|SHF_WRITE|SHF_EXECINSTR.
>
> This patch fixes up the remaining stragglers that were left behind. Add
> Fixes tag so that this doesn't precede related change in stable.
>
> [...]

Applied to arm64 (for-next/core), thanks!

[1/1] arm64: kernel: remove SHF_WRITE|SHF_EXECINSTR from .idmap.text
https://git.kernel.org/arm64/c/4df69e0df295

Cheers,
--
Will

https://fixes.arm64.dev
https://next.arm64.dev
https://will.arm64.dev