diff mbox series

[v3,04/12] linux-user: more debug for init_guest_space

Message ID 20200403191150.863-5-alex.bennee@linaro.org
State Superseded
Headers show
Series a selection of random fixes | expand

Commit Message

Alex Bennée April 3, 2020, 7:11 p.m. UTC
Searching for memory space can cause problems so lets extend the
CPU_LOG_PAGE output so you can watch init_guest_space fail to
allocate memory. A more involved fix is actually required to make this
function play nicely with the large guard pages the sanitiser likes to
use.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

Reviewed-by: Laurent Vivier <laurent@vivier.eu>

---
 linux-user/elfload.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

-- 
2.20.1

Comments

Philippe Mathieu-Daudé April 3, 2020, 8:39 p.m. UTC | #1
On 4/3/20 9:11 PM, Alex Bennée wrote:
> Searching for memory space can cause problems so lets extend the

> CPU_LOG_PAGE output so you can watch init_guest_space fail to

> allocate memory. A more involved fix is actually required to make this

> function play nicely with the large guard pages the sanitiser likes to


TIL "in an effort to differentiate British English from American, many 
British publishers have begun giving -ise endings even to words that 
have always been spelled -ize."

https://grammarist.com/spelling/sanitise-sanitize/

> use.

> 

> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

> Reviewed-by: Laurent Vivier <laurent@vivier.eu>


Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>


> ---

>   linux-user/elfload.c | 8 +++++++-

>   1 file changed, 7 insertions(+), 1 deletion(-)

> 

> diff --git a/linux-user/elfload.c b/linux-user/elfload.c

> index 8198be04460..619c054cc48 100644

> --- a/linux-user/elfload.c

> +++ b/linux-user/elfload.c

> @@ -2172,6 +2172,8 @@ unsigned long init_guest_space(unsigned long host_start,

>   

>           /* Check to see if the address is valid.  */

>           if (host_start && real_start != current_start) {

> +            qemu_log_mask(CPU_LOG_PAGE, "invalid %lx && %lx != %lx\n",

> +                          host_start, real_start, current_start);

>               goto try_again;

>           }

>   

> @@ -2240,7 +2242,11 @@ unsigned long init_guest_space(unsigned long host_start,

>            * probably a bad strategy if not, which means we got here

>            * because of trouble with ARM commpage setup.

>            */

> -        munmap((void *)real_start, real_size);

> +        if (munmap((void *)real_start, real_size) != 0) {

> +            error_report("%s: failed to unmap %lx:%lx (%s)", __func__,

> +                         real_start, real_size, strerror(errno));

> +            abort();

> +        }

>           current_start += align;

>           if (host_start == current_start) {

>               /* Theoretically possible if host doesn't have any suitably

>
diff mbox series

Patch

diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 8198be04460..619c054cc48 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -2172,6 +2172,8 @@  unsigned long init_guest_space(unsigned long host_start,
 
         /* Check to see if the address is valid.  */
         if (host_start && real_start != current_start) {
+            qemu_log_mask(CPU_LOG_PAGE, "invalid %lx && %lx != %lx\n",
+                          host_start, real_start, current_start);
             goto try_again;
         }
 
@@ -2240,7 +2242,11 @@  unsigned long init_guest_space(unsigned long host_start,
          * probably a bad strategy if not, which means we got here
          * because of trouble with ARM commpage setup.
          */
-        munmap((void *)real_start, real_size);
+        if (munmap((void *)real_start, real_size) != 0) {
+            error_report("%s: failed to unmap %lx:%lx (%s)", __func__,
+                         real_start, real_size, strerror(errno));
+            abort();
+        }
         current_start += align;
         if (host_start == current_start) {
             /* Theoretically possible if host doesn't have any suitably