[PATCH] x86: callthunks: fix incorrect init section references

[PATCH] x86: callthunks: fix incorrect init section references

[Arnd Bergmann]

From: Arnd Bergmann <arnd@arndb.de>

The addition of callthunks_translate_call_dest means that
skip_addr() and patch_dest() can no longer be discarded
as part of the __init section freeing:

WARNING: modpost: vmlinux.o: section mismatch in reference: callthunks_translate_call_dest.cold (section: .text.unlikely) -> skip_addr (section: .init.text)
WARNING: modpost: vmlinux.o: section mismatch in reference: callthunks_translate_call_dest.cold (section: .text.unlikely) -> patch_dest (section: .init.text)
WARNING: modpost: vmlinux.o: section mismatch in reference: is_callthunk.cold (section: .text.unlikely) -> skip_addr (section: .init.text)
ERROR: modpost: Section mismatches detected.
Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.

Fixes: b2e9dfe54be4 ("x86/bpf: Emit call depth accounting if required")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 arch/x86/kernel/callthunks.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/callthunks.c b/arch/x86/kernel/callthunks.c
index 7d2c75ec9a8c..ffea98f9064b 100644
--- a/arch/x86/kernel/callthunks.c
+++ b/arch/x86/kernel/callthunks.c
@@ -119,7 +119,7 @@ static bool is_coretext(const struct core_text *ct, void *addr)
 	return within_module_coretext(addr);
 }
 
-static __init_or_module bool skip_addr(void *dest)
+static bool skip_addr(void *dest)
 {
 	if (dest == error_entry)
 		return true;
@@ -181,7 +181,7 @@ static const u8 nops[] = {
 	0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
 };
 
-static __init_or_module void *patch_dest(void *dest, bool direct)
+static void *patch_dest(void *dest, bool direct)
 {
 	unsigned int tsize = SKL_TMPL_SIZE;
 	u8 *pad = dest - tsize;
-- 
2.35.1

Re: [PATCH] x86: callthunks: fix incorrect init section references

[Peter Zijlstra]

On Thu, Dec 15, 2022 at 05:43:23PM +0100, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> The addition of callthunks_translate_call_dest means that
> skip_addr() and patch_dest() can no longer be discarded
> as part of the __init section freeing:
> 
> WARNING: modpost: vmlinux.o: section mismatch in reference: callthunks_translate_call_dest.cold (section: .text.unlikely) -> skip_addr (section: .init.text)
> WARNING: modpost: vmlinux.o: section mismatch in reference: callthunks_translate_call_dest.cold (section: .text.unlikely) -> patch_dest (section: .init.text)
> WARNING: modpost: vmlinux.o: section mismatch in reference: is_callthunk.cold (section: .text.unlikely) -> skip_addr (section: .init.text)
> ERROR: modpost: Section mismatches detected.
> Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.
> 
> Fixes: b2e9dfe54be4 ("x86/bpf: Emit call depth accounting if required")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Thanks!

[tip: x86/urgent] x86/calldepth: Fix incorrect init section references

[tip-bot2 for Arnd Bergmann]

The following commit has been merged into the x86/urgent branch of tip:

Commit-ID:     ade8c20847fcc3f4de08b35f730ec04ef29ddbdc
Gitweb:        https://git.kernel.org/tip/ade8c20847fcc3f4de08b35f730ec04ef29ddbdc
Author:        Arnd Bergmann <arnd@arndb.de>
AuthorDate:    Thu, 15 Dec 2022 17:43:23 +01:00
Committer:     Peter Zijlstra <peterz@infradead.org>
CommitterDate: Tue, 27 Dec 2022 12:51:58 +01:00

x86/calldepth: Fix incorrect init section references

The addition of callthunks_translate_call_dest means that
skip_addr() and patch_dest() can no longer be discarded
as part of the __init section freeing:

WARNING: modpost: vmlinux.o: section mismatch in reference: callthunks_translate_call_dest.cold (section: .text.unlikely) -> skip_addr (section: .init.text)
WARNING: modpost: vmlinux.o: section mismatch in reference: callthunks_translate_call_dest.cold (section: .text.unlikely) -> patch_dest (section: .init.text)
WARNING: modpost: vmlinux.o: section mismatch in reference: is_callthunk.cold (section: .text.unlikely) -> skip_addr (section: .init.text)
ERROR: modpost: Section mismatches detected.
Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.

Fixes: b2e9dfe54be4 ("x86/bpf: Emit call depth accounting if required")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20221215164334.968863-1-arnd@kernel.org
---
 arch/x86/kernel/callthunks.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/callthunks.c b/arch/x86/kernel/callthunks.c
index 7d2c75e..ffea98f 100644
--- a/arch/x86/kernel/callthunks.c
+++ b/arch/x86/kernel/callthunks.c
@@ -119,7 +119,7 @@ static bool is_coretext(const struct core_text *ct, void *addr)
 	return within_module_coretext(addr);
 }
 
-static __init_or_module bool skip_addr(void *dest)
+static bool skip_addr(void *dest)
 {
 	if (dest == error_entry)
 		return true;
@@ -181,7 +181,7 @@ static const u8 nops[] = {
 	0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
 };
 
-static __init_or_module void *patch_dest(void *dest, bool direct)
+static void *patch_dest(void *dest, bool direct)
 {
 	unsigned int tsize = SKL_TMPL_SIZE;
 	u8 *pad = dest - tsize;