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| author |  Christophe Leroy <christophe.leroy@csgroup.eu>
| 2022-12-02 09:31:43 +0100 |
|---|---|---|
| committer |  Michael Ellerman <mpe@ellerman.id.au>
| 2022-12-02 21:59:57 +1100 |
| commit | 6f3a81b60091031c2c14eb2373d1937b027deb46 (patch) | |
| tree | 6185cf59f2c988b5d5f7f5ae943f7968dd88708f /arch/powerpc/lib/code-patching.c | |
| parent | powerpc/feature-fixups: Do not patch init section after init (diff) | |
| download | linux-6f3a81b60091031c2c14eb2373d1937b027deb46.tar.gz linux-6f3a81b60091031c2c14eb2373d1937b027deb46.tar.bz2 linux-6f3a81b60091031c2c14eb2373d1937b027deb46.zip | |
powerpc/code-patching: Remove protection against patching init addresses after init
Once init section is freed, attempting to patch init code
ends up in the weed.
Commit 51c3c62b58b3 ("powerpc: Avoid code patching freed init sections")
protected patch_instruction() against that, but it is the responsibility
of the caller to ensure that the patched memory is valid.
All callers have now been verified and fixed so the check
can be removed.
This improves ftrace activation by about 2% on 8xx.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/504310828f473d424e2ed229eff57bf075f52796.1669969781.git.christophe.leroy@csgroup.eu
Diffstat (limited to 'arch/powerpc/lib/code-patching.c')
| -rw-r--r-- | arch/powerpc/lib/code-patching.c | 13 |
1 files changed, 1 insertions, 12 deletions
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c index a6a5047f8ba2..73ce4b90bb1b 100644 --- a/arch/powerpc/lib/code-patching.c +++ b/arch/powerpc/lib/code-patching.c @@ -349,7 +349,7 @@ static int __do_patch_instruction(u32 *addr, ppc_inst_t instr) return err; } -static int do_patch_instruction(u32 *addr, ppc_inst_t instr) +int patch_instruction(u32 *addr, ppc_inst_t instr) { int err; unsigned long flags; @@ -372,17 +372,6 @@ static int do_patch_instruction(u32 *addr, ppc_inst_t instr) return err; } - -__ro_after_init DEFINE_STATIC_KEY_FALSE(init_mem_is_free); - -int patch_instruction(u32 *addr, ppc_inst_t instr) -{ - /* Make sure we aren't patching a freed init section */ - if (static_branch_likely(&init_mem_is_free) && init_section_contains(addr, 4)) - return 0; - - return do_patch_instruction(addr, instr); -} NOKPROBE_SYMBOL(patch_instruction); int patch_branch(u32 *addr, unsigned long target, int flags) |