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Diffstat (limited to 'arch/x86/kernel/paravirt.c')
-rw-r--r--arch/x86/kernel/paravirt.c46
1 files changed, 23 insertions, 23 deletions
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index 06f6bb48d018..98039d7fb998 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -58,24 +58,24 @@ struct branch {
u32 delta;
} __attribute__((packed));
-static unsigned paravirt_patch_call(void *insnbuf, const void *target,
+static unsigned paravirt_patch_call(void *insn_buff, const void *target,
unsigned long addr, unsigned len)
{
- struct branch *b = insnbuf;
- unsigned long delta = (unsigned long)target - (addr+5);
-
- if (len < 5) {
-#ifdef CONFIG_RETPOLINE
- WARN_ONCE(1, "Failing to patch indirect CALL in %ps\n", (void *)addr);
-#endif
- return len; /* call too long for patch site */
+ const int call_len = 5;
+ struct branch *b = insn_buff;
+ unsigned long delta = (unsigned long)target - (addr+call_len);
+
+ if (len < call_len) {
+ pr_warn("paravirt: Failed to patch indirect CALL at %ps\n", (void *)addr);
+ /* Kernel might not be viable if patching fails, bail out: */
+ BUG_ON(1);
}
b->opcode = 0xe8; /* call */
b->delta = delta;
- BUILD_BUG_ON(sizeof(*b) != 5);
+ BUILD_BUG_ON(sizeof(*b) != call_len);
- return 5;
+ return call_len;
}
#ifdef CONFIG_PARAVIRT_XXL
@@ -85,10 +85,10 @@ u64 notrace _paravirt_ident_64(u64 x)
return x;
}
-static unsigned paravirt_patch_jmp(void *insnbuf, const void *target,
+static unsigned paravirt_patch_jmp(void *insn_buff, const void *target,
unsigned long addr, unsigned len)
{
- struct branch *b = insnbuf;
+ struct branch *b = insn_buff;
unsigned long delta = (unsigned long)target - (addr+5);
if (len < 5) {
@@ -113,7 +113,7 @@ void __init native_pv_lock_init(void)
static_branch_disable(&virt_spin_lock_key);
}
-unsigned paravirt_patch_default(u8 type, void *insnbuf,
+unsigned paravirt_patch_default(u8 type, void *insn_buff,
unsigned long addr, unsigned len)
{
/*
@@ -125,36 +125,36 @@ unsigned paravirt_patch_default(u8 type, void *insnbuf,
if (opfunc == NULL)
/* If there's no function, patch it with a ud2a (BUG) */
- ret = paravirt_patch_insns(insnbuf, len, ud2a, ud2a+sizeof(ud2a));
+ ret = paravirt_patch_insns(insn_buff, len, ud2a, ud2a+sizeof(ud2a));
else if (opfunc == _paravirt_nop)
ret = 0;
#ifdef CONFIG_PARAVIRT_XXL
/* identity functions just return their single argument */
else if (opfunc == _paravirt_ident_64)
- ret = paravirt_patch_ident_64(insnbuf, len);
+ ret = paravirt_patch_ident_64(insn_buff, len);
else if (type == PARAVIRT_PATCH(cpu.iret) ||
type == PARAVIRT_PATCH(cpu.usergs_sysret64))
/* If operation requires a jmp, then jmp */
- ret = paravirt_patch_jmp(insnbuf, opfunc, addr, len);
+ ret = paravirt_patch_jmp(insn_buff, opfunc, addr, len);
#endif
else
/* Otherwise call the function. */
- ret = paravirt_patch_call(insnbuf, opfunc, addr, len);
+ ret = paravirt_patch_call(insn_buff, opfunc, addr, len);
return ret;
}
-unsigned paravirt_patch_insns(void *insnbuf, unsigned len,
+unsigned paravirt_patch_insns(void *insn_buff, unsigned len,
const char *start, const char *end)
{
unsigned insn_len = end - start;
- if (insn_len > len || start == NULL)
- insn_len = len;
- else
- memcpy(insnbuf, start, insn_len);
+ /* Alternative instruction is too large for the patch site and we cannot continue: */
+ BUG_ON(insn_len > len || start == NULL);
+
+ memcpy(insn_buff, start, insn_len);
return insn_len;
}