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author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-08-16 10:51:47 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-08-16 10:51:47 -0700 |
commit | b7e7c85dc7b0ea5ff821756c331489e3b151eed1 (patch) | |
tree | 60113a949e3a35025323e7fe8e45fb62b1a9c87d /arch/arm64 | |
parent | 2d63ba3e41db3ceb0d23924ed2879b910276e24c (diff) | |
parent | b6143d10d23ebb4a77af311e8b8b7f019d0163e6 (diff) | |
download | linux-b7e7c85dc7b0ea5ff821756c331489e3b151eed1.tar.gz linux-b7e7c85dc7b0ea5ff821756c331489e3b151eed1.tar.bz2 linux-b7e7c85dc7b0ea5ff821756c331489e3b151eed1.zip |
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Catalin Marinas:
- Don't taint the kernel if CPUs have different sets of page sizes
supported (other than the one in use).
- Issue I-cache maintenance for module ftrace trampoline.
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: ftrace: Ensure module ftrace trampoline is coherent with I-side
arm64: cpufeature: Don't treat granule sizes as strict
Diffstat (limited to 'arch/arm64')
-rw-r--r-- | arch/arm64/kernel/cpufeature.c | 14 | ||||
-rw-r--r-- | arch/arm64/kernel/ftrace.c | 22 |
2 files changed, 24 insertions, 12 deletions
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index d19d14ba9ae4..b1fdc486aed8 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -184,9 +184,17 @@ static const struct arm64_ftr_bits ftr_id_aa64zfr0[] = { }; static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = { - S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI), - S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI), - ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI), + /* + * We already refuse to boot CPUs that don't support our configured + * page size, so we can only detect mismatches for a page size other + * than the one we're currently using. Unfortunately, SoCs like this + * exist in the wild so, even though we don't like it, we'll have to go + * along with it and treat them as non-strict. + */ + S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI), + S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI), + ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI), + ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0), /* Linux shouldn't care about secure memory */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0), diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c index 1285c7b2947f..171773257974 100644 --- a/arch/arm64/kernel/ftrace.c +++ b/arch/arm64/kernel/ftrace.c @@ -73,7 +73,7 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) if (offset < -SZ_128M || offset >= SZ_128M) { #ifdef CONFIG_ARM64_MODULE_PLTS - struct plt_entry trampoline; + struct plt_entry trampoline, *dst; struct module *mod; /* @@ -106,23 +106,27 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) * to check if the actual opcodes are in fact identical, * regardless of the offset in memory so use memcmp() instead. */ - trampoline = get_plt_entry(addr, mod->arch.ftrace_trampoline); - if (memcmp(mod->arch.ftrace_trampoline, &trampoline, - sizeof(trampoline))) { - if (plt_entry_is_initialized(mod->arch.ftrace_trampoline)) { + dst = mod->arch.ftrace_trampoline; + trampoline = get_plt_entry(addr, dst); + if (memcmp(dst, &trampoline, sizeof(trampoline))) { + if (plt_entry_is_initialized(dst)) { pr_err("ftrace: far branches to multiple entry points unsupported inside a single module\n"); return -EINVAL; } /* point the trampoline to our ftrace entry point */ module_disable_ro(mod); - *mod->arch.ftrace_trampoline = trampoline; + *dst = trampoline; module_enable_ro(mod, true); - /* update trampoline before patching in the branch */ - smp_wmb(); + /* + * Ensure updated trampoline is visible to instruction + * fetch before we patch in the branch. + */ + __flush_icache_range((unsigned long)&dst[0], + (unsigned long)&dst[1]); } - addr = (unsigned long)(void *)mod->arch.ftrace_trampoline; + addr = (unsigned long)dst; #else /* CONFIG_ARM64_MODULE_PLTS */ return -EINVAL; #endif /* CONFIG_ARM64_MODULE_PLTS */ |