2023-07-11 13:44:35

by Petr Pavlu

Subject: [PATCH] vmlinux.lds.h: Remove a reference to no longer used sections .text..refcount

Sections .text..refcount were previously used to hold an error path code
for fast refcount overflow protection on x86, see commit 7a46ec0e2f48
("locking/refcounts, x86/asm: Implement fast refcount overflow
protection") and commit 564c9cc84e2a ("locking/refcounts, x86/asm: Use
unique .text section for refcount exceptions").

The code was replaced and removed in commit fb041bb7c0a9
("locking/refcount: Consolidate implementations of refcount_t") and no
sections .text..refcount are present since then.

Remove then a relic referencing these sections from TEXT_TEXT to avoid
confusing people, like me. This is a non-functional change.

Signed-off-by: Petr Pavlu <[email protected]>
---
include/asm-generic/vmlinux.lds.h | 1 -
1 file changed, 1 deletion(-)

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index 0587354ba678..9c59409104f6 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -578,7 +578,6 @@
*(.text.unlikely .text.unlikely.*) \
*(.text.unknown .text.unknown.*) \
NOINSTR_TEXT \
- *(.text..refcount) \
*(.ref.text) \
*(.text.asan.* .text.tsan.*) \
MEM_KEEP(init.text*) \
--
2.35.3

2023-07-11 22:04:01

by Kees Cook

Subject: Re: [PATCH] vmlinux.lds.h: Remove a reference to no longer used sections .text..refcount

On Tue, 11 Jul 2023 14:50:54 +0200, Petr Pavlu wrote:
> Sections .text..refcount were previously used to hold an error path code
> for fast refcount overflow protection on x86, see commit 7a46ec0e2f48
> ("locking/refcounts, x86/asm: Implement fast refcount overflow
> protection") and commit 564c9cc84e2a ("locking/refcounts, x86/asm: Use
> unique .text section for refcount exceptions").
>
> The code was replaced and removed in commit fb041bb7c0a9
> ("locking/refcount: Consolidate implementations of refcount_t") and no
> sections .text..refcount are present since then.
>
> [...]

Applied, thanks!

[1/1] vmlinux.lds.h: Remove a reference to no longer used sections .text..refcount
https://git.kernel.org/kees/c/5fc522485598

Best regards,
--
Kees Cook