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Subject[PATCH v3] kprobes: remove duplicated strong free_insn_page in x86 and s390
Date
free_insn_page() in x86 and s390 is same with the common weak function
in kernel/kprobes.c.
Plus, the comment "Recover page to RW mode before releasing it" in x86
seems insensible to be there since resetting mapping is done by common
code in vfree() of module_memfree().
So drop these two duplicated strong functions and related comment, then
mark the common one in kernel/kprobes.c strong.

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
---
-v3: mark free_insn_page as static according to Christoph's comment

arch/s390/kernel/kprobes.c | 5 -----
arch/x86/kernel/kprobes/core.c | 6 ------
include/linux/kprobes.h | 1 -
kernel/kprobes.c | 2 +-
4 files changed, 1 insertion(+), 13 deletions(-)

diff --git a/arch/s390/kernel/kprobes.c b/arch/s390/kernel/kprobes.c
index aae24dc75df6..60cfbd24229b 100644
--- a/arch/s390/kernel/kprobes.c
+++ b/arch/s390/kernel/kprobes.c
@@ -44,11 +44,6 @@ void *alloc_insn_page(void)
return page;
}

-void free_insn_page(void *page)
-{
- module_memfree(page);
-}
-
static void *alloc_s390_insn_page(void)
{
if (xchg(&insn_page_in_use, 1) == 1)
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index d3d65545cb8b..3bce67d3a03c 100644
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -422,12 +422,6 @@ void *alloc_insn_page(void)
return page;
}

-/* Recover page to RW mode before releasing it */
-void free_insn_page(void *page)
-{
- module_memfree(page);
-}
-
/* Kprobe x86 instruction emulation - only regs->ip or IF flag modifiers */

static void kprobe_emulate_ifmodifiers(struct kprobe *p, struct pt_regs *regs)
diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index 1883a4a9f16a..c98a35a75f40 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -407,7 +407,6 @@ int enable_kprobe(struct kprobe *kp);
void dump_kprobe(struct kprobe *kp);

void *alloc_insn_page(void);
-void free_insn_page(void *page);

int kprobe_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
char *sym);
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 745f08fdd7a6..e0c4c9d57299 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -106,7 +106,7 @@ void __weak *alloc_insn_page(void)
return module_alloc(PAGE_SIZE);
}

-void __weak free_insn_page(void *page)
+static void free_insn_page(void *page)
{
module_memfree(page);
}
--
2.25.1
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