diff mbox series

[4/5] accel/tcg: Avoid using lock_user() in cpu_memory_rw_debug()

Message ID 20250217130610.18313-5-philmd@linaro.org
State New
Headers show
Series accel/tcg: Clean cpu_memory_rw_debug() up | expand

Commit Message

Philippe Mathieu-Daudé Feb. 17, 2025, 1:06 p.m. UTC 
We checked the page flags with page_get_flags(), so
locking the page is superfluous. Remove the lock_user()
calls and directly use g2h() in place.

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 cpu-target.c | 17 ++---------------
 1 file changed, 2 insertions(+), 15 deletions(-)

Comments

Richard Henderson Feb. 17, 2025, 7:39 p.m. UTC | #1 
On 2/17/25 05:06, Philippe Mathieu-Daudé wrote:
> We checked the page flags with page_get_flags(), so
> locking the page is superfluous. Remove the lock_user()
> calls and directly use g2h() in place.
> 
> Suggested-by: Richard Henderson<richard.henderson@linaro.org>
> Signed-off-by: Philippe Mathieu-Daudé<philmd@linaro.org>
> ---
>   cpu-target.c | 17 ++---------------
>   1 file changed, 2 insertions(+), 15 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~
diff mbox series

Patch

diff --git a/cpu-target.c b/cpu-target.c
index b5230ce1837..3892ce12229 100644
--- a/cpu-target.c
+++ b/cpu-target.c
@@ -374,7 +374,6 @@  int cpu_memory_rw_debug(CPUState *cpu, vaddr addr,
 {
     int flags;
     vaddr l, page;
-    void * p;
     uint8_t *buf = ptr;
     ssize_t written;
     int ret = -1;
@@ -393,13 +392,7 @@  int cpu_memory_rw_debug(CPUState *cpu, vaddr addr,
         }
         if (is_write) {
             if (flags & PAGE_WRITE) {
-                /* XXX: this code should not depend on lock_user */
-                p = lock_user(VERIFY_WRITE, addr, l, 0);
-                if (!p) {
-                    goto out_close;
-                }
-                memcpy(p, buf, l);
-                unlock_user(p, addr, l);
+                memcpy(g2h(cpu, addr), buf, l);
             } else {
                 /* Bypass the host page protection using ptrace. */
                 if (fd == -1) {
@@ -424,13 +417,7 @@  int cpu_memory_rw_debug(CPUState *cpu, vaddr addr,
                 }
             }
         } else if (flags & PAGE_READ) {
-            /* XXX: this code should not depend on lock_user */
-            p = lock_user(VERIFY_READ, addr, l, 1);
-            if (!p) {
-                goto out_close;
-            }
-            memcpy(buf, p, l);
-            unlock_user(p, addr, 0);
+            memcpy(buf, g2h(cpu, addr), l);
         } else {
             /* Bypass the host page protection using ptrace. */
             if (fd == -1) {