[PATCH v2 2/3] dump: add crash_occurred flag to QEMUCPUState

Add is_crash_occurred_cpu field to QEMUCPUState so that
dump-guest-memory can record which CPU triggered the guest
panic.

The new field is appended after kernel_gs_base, so existing
tools that check the 'size' field can safely ignore it when
reading older dumps.

Changes since v1:
  - Revert QEMUCPUSTATE_VERSION bump (not needed, tools check size)
  - Move crash_occurred check outside #ifdef TARGET_X86_64 to fix
    -Werror=unused-variable on i386 builds (reported by Akihiko Odaki)
  - Use linux.alibaba.com identity

Signed-off-by: Zhengrong Li <[email protected]>
---
 contrib/elf2dmp/qemu_elf.h | 2 ++
 target/i386/arch_dump.c    | 6 ++++++
 2 files changed, 8 insertions(+)

diff --git a/contrib/elf2dmp/qemu_elf.h b/contrib/elf2dmp/qemu_elf.h
index adc50238b4..3b28332e67 100644
--- a/contrib/elf2dmp/qemu_elf.h
+++ b/contrib/elf2dmp/qemu_elf.h
@@ -27,6 +27,8 @@ typedef struct QEMUCPUState {
     QEMUCPUSegment ldt, tr, gdt, idt;
     uint64_t cr[5];
     uint64_t kernel_gs_base;
+    uint8_t  is_crash_occurred_cpu;
+    uint8_t  pad[7];
 } QEMUCPUState;
 
 int is_system(QEMUCPUState *s);
diff --git a/target/i386/arch_dump.c b/target/i386/arch_dump.c
index 16e47c4747..8ce2c7e9bb 100644
--- a/target/i386/arch_dump.c
+++ b/target/i386/arch_dump.c
@@ -264,6 +264,8 @@ struct QEMUCPUState {
      * by checking 'size' field.
      */
     uint64_t kernel_gs_base;
+    uint8_t  is_crash_occurred_cpu;
+    uint8_t  pad[7];
 };
 
 typedef struct QEMUCPUState QEMUCPUState;
@@ -279,6 +281,7 @@ static void copy_segment(QEMUCPUSegment *d, SegmentCache *s)
 
 static void qemu_get_cpustate(QEMUCPUState *s, CPUX86State *env)
 {
+    CPUState *cs = env_cpu(env);
     memset(s, 0, sizeof(QEMUCPUState));
 
     s->version = QEMUCPUSTATE_VERSION;
@@ -325,6 +328,9 @@ static void qemu_get_cpustate(QEMUCPUState *s, CPUX86State *env)
 #ifdef TARGET_X86_64
     s->kernel_gs_base = env->kernelgsbase;
 #endif
+    if (cs->crash_occurred) {
+        s->is_crash_occurred_cpu = 1;
+    }
 }
 
 static inline int cpu_write_qemu_note(WriteCoreDumpFunction f,
-- 
2.43.0