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| author | Christophe Leroy <christophe.leroy@csgroup.eu> | 2022-12-02 09:31:42 +0100 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2022-12-02 21:59:57 +1100 |
| commit | b988e7797d09379057cf991ae082f9ad7a309a63 (patch) | |
| tree | ee80cecd3e52021109a0bed6f09b1a4fe200b926 /arch/powerpc/lib | |
| parent | 3d1dbbca33a9c6dd3aafd4d14aaea9cc310723e1 (diff) | |
| download | linux-b988e7797d09379057cf991ae082f9ad7a309a63.tar.gz linux-b988e7797d09379057cf991ae082f9ad7a309a63.tar.bz2 linux-b988e7797d09379057cf991ae082f9ad7a309a63.zip | |
powerpc/feature-fixups: Do not patch init section 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.
In the same spirit as jump_label with its jump_label_can_update()
function, add is_fixup_addr_valid() function to skip patching on
freed init section.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8e9311fc1b057e4e6a2a3a0701ebcc74b787affe.1669969781.git.christophe.leroy@csgroup.eu
Diffstat (limited to 'arch/powerpc/lib')
| -rw-r--r-- | arch/powerpc/lib/feature-fixups.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/powerpc/lib/feature-fixups.c b/arch/powerpc/lib/feature-fixups.c index 25168a59d1ce..80def1c2afcb 100644 --- a/arch/powerpc/lib/feature-fixups.c +++ b/arch/powerpc/lib/feature-fixups.c @@ -118,6 +118,12 @@ void do_feature_fixups(unsigned long value, void *fixup_start, void *fixup_end) } #ifdef CONFIG_PPC_BARRIER_NOSPEC +static bool is_fixup_addr_valid(void *dest, size_t size) +{ + return system_state < SYSTEM_FREEING_INITMEM || + !init_section_contains(dest, size); +} + static int do_patch_fixups(long *start, long *end, unsigned int *instrs, int num) { int i; @@ -126,6 +132,9 @@ static int do_patch_fixups(long *start, long *end, unsigned int *instrs, int num int j; unsigned int *dest = (void *)start + *start; + if (!is_fixup_addr_valid(dest, sizeof(*instrs) * num)) + continue; + pr_devel("patching dest %lx\n", (unsigned long)dest); for (j = 0; j < num; j++) @@ -144,6 +153,9 @@ static int do_patch_entry_fixups(long *start, long *end, unsigned int *instrs, for (i = 0; start < end; start++, i++) { unsigned int *dest = (void *)start + *start; + if (!is_fixup_addr_valid(dest, sizeof(*instrs) * 3)) + continue; + pr_devel("patching dest %lx\n", (unsigned long)dest); // See comment in do_entry_flush_fixups() RE order of patching |