Modules being loaded using perm_allocs may have a separate writable
address. Handle this case in alternatives for operations called during
module loading.
Signed-off-by: Rick Edgecombe <rick.p.edgeco...@intel.com>
---
arch/x86/kernel/alternative.c | 25 ++++++++++++++++---------
1 file changed, 16 insertions(+), 9 deletions(-)
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index 2400ad62f330..e6d8a696540b 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -373,7 +373,7 @@ void __init_or_module noinline apply_alternatives(struct
alt_instr *start,
struct alt_instr *end)
{
struct alt_instr *a;
- u8 *instr, *replacement;
+ u8 *instr, *writ_instr, *replacement, *writ_replacement;
u8 insn_buff[MAX_PATCH_LEN];
DPRINTK("alt table %px, -> %px", start, end);
@@ -391,11 +391,13 @@ void __init_or_module noinline apply_alternatives(struct
alt_instr *start,
instr = (u8 *)&a->instr_offset + a->instr_offset;
replacement = (u8 *)&a->repl_offset + a->repl_offset;
+ writ_instr = (u8 *)module_adjust_writable_addr(instr);
+ writ_replacement = (u8
*)module_adjust_writable_addr(replacement);
BUG_ON(a->instrlen > sizeof(insn_buff));
BUG_ON(a->cpuid >= (NCAPINTS + NBUGINTS) * 32);
if (!boot_cpu_has(a->cpuid)) {
if (a->padlen > 1)
- optimize_nops(a, instr);
+ optimize_nops(a, writ_instr);
continue;
}
@@ -403,13 +405,13 @@ void __init_or_module noinline apply_alternatives(struct
alt_instr *start,
DPRINTK("feat: %d*32+%d, old: (%pS (%px) len: %d), repl: (%px,
len: %d), pad: %d",
a->cpuid >> 5,
a->cpuid & 0x1f,
- instr, instr, a->instrlen,
+ writ_instr, instr, a->instrlen,
replacement, a->replacementlen, a->padlen);
DUMP_BYTES(instr, a->instrlen, "%px: old_insn: ", instr);
DUMP_BYTES(replacement, a->replacementlen, "%px: rpl_insn: ",
replacement);
- memcpy(insn_buff, replacement, a->replacementlen);
+ memcpy(insn_buff, writ_replacement, a->replacementlen);
insn_buff_sz = a->replacementlen;
/*
@@ -435,7 +437,7 @@ void __init_or_module noinline apply_alternatives(struct
alt_instr *start,
}
DUMP_BYTES(insn_buff, insn_buff_sz, "%px: final_insn: ", instr);
- text_poke_early(instr, insn_buff, insn_buff_sz);
+ text_poke_early(writ_instr, insn_buff, insn_buff_sz);
}
}
@@ -496,6 +498,10 @@ void __init_or_module alternatives_smp_module_add(struct
module *mod,
void *text, void *text_end)
{
struct smp_alt_module *smp;
+ void *w_locks = module_adjust_writable_addr(locks);
+ void *w_locks_end = module_adjust_writable_addr(locks_end);
+ void *w_text = module_adjust_writable_addr(text);
+ void *w_text_end = module_adjust_writable_addr(text_end);
mutex_lock(&text_mutex);
if (!uniproc_patched)
@@ -522,7 +528,7 @@ void __init_or_module alternatives_smp_module_add(struct
module *mod,
list_add_tail(&smp->next, &smp_alt_modules);
smp_unlock:
- alternatives_smp_unlock(locks, locks_end, text, text_end);
+ alternatives_smp_unlock(w_locks, w_locks_end, w_text, w_text_end);
unlock:
mutex_unlock(&text_mutex);
}
@@ -601,17 +607,18 @@ void __init_or_module apply_paravirt(struct
paravirt_patch_site *start,
for (p = start; p < end; p++) {
unsigned int used;
+ void *writable = module_adjust_writable_addr(p->instr);
BUG_ON(p->len > MAX_PATCH_LEN);
/* prep the buffer with the original instructions */
- memcpy(insn_buff, p->instr, p->len);
- used = pv_ops.init.patch(p->type, insn_buff, (unsigned
long)p->instr, p->len);
+ memcpy(insn_buff, writable, p->len);
+ used = pv_ops.init.patch(p->type, insn_buff, (unsigned
long)writable, p->len);
BUG_ON(used > p->len);
/* Pad the rest with nops */
add_nops(insn_buff + used, p->len - used);
- text_poke_early(p->instr, insn_buff, p->len);
+ text_poke_early(writable, insn_buff, p->len);
}
}
extern struct paravirt_patch_site __start_parainstructions[],
--
2.20.1
