diff mbox

[1/1] dump: Update correct kdump phys_base field for AArch64

Message ID 1520615003-20869-1-git-send-email-wei@redhat.com (mailing list archive)
State New, archived
Headers show

Commit Message

Wei Huang March 9, 2018, 5:03 p.m. UTC
For guest kernel that supports KASLR, the load address can change every
time when guest VM runs. To find the physical base address correctly,
current QEMU dump searches VMCOREINFO for the string "NUMBER(phys_base)=".
However this string pattern is only available on x86_64. AArch64 uses a
different field, called "NUMBER(PHYS_OFFSET)=". This patch makes sure
QEMU dump uses the correct string on AArch64.

Signed-off-by: Wei Huang <wei@redhat.com>
---
 dump.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

Comments

Marc-André Lureau March 11, 2018, 5:42 p.m. UTC | #1
Hi

On Fri, Mar 9, 2018 at 6:03 PM, Wei Huang <wei@redhat.com> wrote:
> For guest kernel that supports KASLR, the load address can change every
> time when guest VM runs. To find the physical base address correctly,
> current QEMU dump searches VMCOREINFO for the string "NUMBER(phys_base)=".
> However this string pattern is only available on x86_64. AArch64 uses a
> different field, called "NUMBER(PHYS_OFFSET)=". This patch makes sure
> QEMU dump uses the correct string on AArch64.
>
> Signed-off-by: Wei Huang <wei@redhat.com>

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>


> ---
>  dump.c | 14 +++++++++++---
>  1 file changed, 11 insertions(+), 3 deletions(-)
>
> diff --git a/dump.c b/dump.c
> index 097e60b..6bdb0db 100644
> --- a/dump.c
> +++ b/dump.c
> @@ -1609,10 +1609,18 @@ static void vmcoreinfo_update_phys_base(DumpState *s)
>
>      lines = g_strsplit((char *)vmci, "\n", -1);
>      for (i = 0; lines[i]; i++) {
> -        if (g_str_has_prefix(lines[i], "NUMBER(phys_base)=")) {
> -            if (qemu_strtou64(lines[i] + 18, NULL, 16,
> +        const char *prefix = NULL;
> +
> +        if (s->dump_info.d_machine == EM_X86_64) {
> +            prefix = "NUMBER(phys_base)=";
> +        } else if (s->dump_info.d_machine == EM_AARCH64) {
> +            prefix = "NUMBER(PHYS_OFFSET)=";
> +        }
> +
> +        if (prefix && g_str_has_prefix(lines[i], prefix)) {
> +            if (qemu_strtou64(lines[i] + strlen(prefix), NULL, 16,
>                                &phys_base) < 0) {
> -                warn_report("Failed to read NUMBER(phys_base)=");
> +                warn_report("Failed to read %s", prefix);
>              } else {
>                  s->dump_info.phys_base = phys_base;
>              }
> --
> 1.8.3.1
>
Peter Maydell March 12, 2018, 1:45 p.m. UTC | #2
On 11 March 2018 at 17:42, Marc-André Lureau
<marcandre.lureau@redhat.com> wrote:
> Hi
>
> On Fri, Mar 9, 2018 at 6:03 PM, Wei Huang <wei@redhat.com> wrote:
>> For guest kernel that supports KASLR, the load address can change every
>> time when guest VM runs. To find the physical base address correctly,
>> current QEMU dump searches VMCOREINFO for the string "NUMBER(phys_base)=".
>> However this string pattern is only available on x86_64. AArch64 uses a
>> different field, called "NUMBER(PHYS_OFFSET)=". This patch makes sure
>> QEMU dump uses the correct string on AArch64.
>>
>> Signed-off-by: Wei Huang <wei@redhat.com>
>
> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>

Thanks; applied to target-arm.next for 2.12.

-- PMM
diff mbox

Patch

diff --git a/dump.c b/dump.c
index 097e60b..6bdb0db 100644
--- a/dump.c
+++ b/dump.c
@@ -1609,10 +1609,18 @@  static void vmcoreinfo_update_phys_base(DumpState *s)
 
     lines = g_strsplit((char *)vmci, "\n", -1);
     for (i = 0; lines[i]; i++) {
-        if (g_str_has_prefix(lines[i], "NUMBER(phys_base)=")) {
-            if (qemu_strtou64(lines[i] + 18, NULL, 16,
+        const char *prefix = NULL;
+
+        if (s->dump_info.d_machine == EM_X86_64) {
+            prefix = "NUMBER(phys_base)=";
+        } else if (s->dump_info.d_machine == EM_AARCH64) {
+            prefix = "NUMBER(PHYS_OFFSET)=";
+        }
+
+        if (prefix && g_str_has_prefix(lines[i], prefix)) {
+            if (qemu_strtou64(lines[i] + strlen(prefix), NULL, 16,
                               &phys_base) < 0) {
-                warn_report("Failed to read NUMBER(phys_base)=");
+                warn_report("Failed to read %s", prefix);
             } else {
                 s->dump_info.phys_base = phys_base;
             }