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authorPu Lehui <[email protected]>2023-02-15 21:52:02 +0800
committerDaniel Borkmann <[email protected]>2023-02-17 21:45:30 +0100
commit5e57fb7b0bd3ea7e994ef1c0ab3562d1fe0676b2 (patch)
tree150dfe4d1f95aec03c11f35144a27cb39bf117e5 /arch/riscv/kernel/patch.c
parent181127fb76e62d06ab17a75fd610129688612343 (diff)
riscv: Extend patch_text for multiple instructions
Extend patch_text for multiple instructions. This is the preparaiton for multiple instructions text patching in riscv BPF trampoline, and may be useful for other scenario. Signed-off-by: Pu Lehui <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Tested-by: Björn Töpel <[email protected]> Reviewed-by: Conor Dooley <[email protected]> Acked-by: Björn Töpel <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
Diffstat (limited to 'arch/riscv/kernel/patch.c')
-rw-r--r--arch/riscv/kernel/patch.c19
1 files changed, 12 insertions, 7 deletions
diff --git a/arch/riscv/kernel/patch.c b/arch/riscv/kernel/patch.c
index 765004b60513..8086d1a281cd 100644
--- a/arch/riscv/kernel/patch.c
+++ b/arch/riscv/kernel/patch.c
@@ -15,7 +15,8 @@
struct patch_insn {
void *addr;
- u32 insn;
+ u32 *insns;
+ int ninsns;
atomic_t cpu_count;
};
@@ -102,12 +103,15 @@ NOKPROBE_SYMBOL(patch_text_nosync);
static int patch_text_cb(void *data)
{
struct patch_insn *patch = data;
- int ret = 0;
+ unsigned long len;
+ int i, ret = 0;
if (atomic_inc_return(&patch->cpu_count) == num_online_cpus()) {
- ret =
- patch_text_nosync(patch->addr, &patch->insn,
- GET_INSN_LENGTH(patch->insn));
+ for (i = 0; ret == 0 && i < patch->ninsns; i++) {
+ len = GET_INSN_LENGTH(patch->insns[i]);
+ ret = patch_text_nosync(patch->addr + i * len,
+ &patch->insns[i], len);
+ }
atomic_inc(&patch->cpu_count);
} else {
while (atomic_read(&patch->cpu_count) <= num_online_cpus())
@@ -119,11 +123,12 @@ static int patch_text_cb(void *data)
}
NOKPROBE_SYMBOL(patch_text_cb);
-int patch_text(void *addr, u32 insn)
+int patch_text(void *addr, u32 *insns, int ninsns)
{
struct patch_insn patch = {
.addr = addr,
- .insn = insn,
+ .insns = insns,
+ .ninsns = ninsns,
.cpu_count = ATOMIC_INIT(0),
};