leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

powerpc/ftrace: Add support for livepatch to PPC32

Browse Source 
PPC64 needs some special logic to properly set up the TOC.
See commit 85baa09549 ("powerpc/livepatch: Add live patching support
on ppc64le") for details.

PPC32 doesn't have TOC so it doesn't need that logic, so adding
LIVEPATCH support is straight forward.

Add CONFIG_LIVEPATCH_64 and move livepatch stack logic into that item.

Livepatch sample modules all work.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/63cb094125b6a6038c65eeac2abaabbabe63addd.1640017960.git.christophe.leroy@csgroup.eu
This commit is contained in:
Christophe Leroy
2021-12-20 16:38:12 +00:00
committed by Michael Ellerman
parent 0c850965d6
commit a4520b2527
4 changed files with 12 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
arch/powerpc/include/asm/livepatch.h
View File

@@ -23,12 +23,14 @@ static inline void klp_arch_set_pc(struct ftrace_regs *fregs, unsigned long ip)
static inline unsigned long klp_get_ftrace_location(unsigned long faddr)
{
/*
* Live patch works only with -mprofile-kernel on PPC. In this case,
* the ftrace location is always within the first 16 bytes.
* Live patch works on PPC32 and only with -mprofile-kernel on PPC64. In
* both cases, the ftrace location is always within the first 16 bytes.
*/
return ftrace_location_range(faddr, faddr + 16);
}
#endif /* CONFIG_LIVEPATCH */
#ifdef CONFIG_LIVEPATCH_64
static inline void klp_init_thread_info(struct task_struct *p)
{
/* + 1 to account for STACK_END_MAGIC */
@@ -36,6 +38,6 @@ static inline void klp_init_thread_info(struct task_struct *p)
}
#else
static inline void klp_init_thread_info(struct task_struct *p) { }
#endif /* CONFIG_LIVEPATCH */
#endif
#endif /* _ASM_POWERPC_LIVEPATCH_H */