[v2] target/ppc/arch_dump: set prstatus pid to cpuid

Commit Message

Omar Sandoval July 1, 2024, 4:51 p.m. UTC

Every other architecture does this, and debuggers need it to be able to
identify which prstatus note corresponds to which CPU.

Reviewed-by: Harsh Prateek Bora <[e-mail]>
Signed-off-by: Omar Sandoval <[e-mail]>
---
This is v2 from my small series [1] making QEMU fill the pr_pid field of
the NT_PRSTATUS note consistently.

Changes from v1:

- Add comments explaning sizes of padding fields.

1: https://lore.kernel.org/qemu-devel/[e-mail]/

 target/ppc/arch_dump.c | 24 +++++++++++++++---------
 1 file changed, 15 insertions(+), 9 deletions(-)

Comments

Omar Sandoval July 1, 2024, 9:23 p.m. UTC | #1

On Mon, Jul 01, 2024 at 09:51:35AM -0700, Omar Sandoval wrote:
> Every other architecture does this, and debuggers need it to be able to
> identify which prstatus note corresponds to which CPU.
> 
> Reviewed-by: Harsh Prateek Bora <[e-mail]>

Oops, I forgot to copy Thomas's reviewed-by from v1:

Reviewed-by: Thomas Huth <[e-mail]>

> Signed-off-by: Omar Sandoval <[e-mail]>

Patch

diff --git a/target/ppc/arch_dump.c b/target/ppc/arch_dump.c
index a8315659d9..ff93cac61e 100644
--- a/target/ppc/arch_dump.c
+++ b/target/ppc/arch_dump.c
@@ -47,9 +47,14 @@  struct PPCUserRegStruct {
 } QEMU_PACKED;
 
 struct PPCElfPrstatus {
-    char pad1[112];
+    char pad1[32]; /* 32 == offsetof(struct elf_prstatus, pr_pid) */
+    uint32_t pid;
+    char pad2[76]; /* 76 == offsetof(struct elf_prstatus, pr_reg) -
+                            offsetof(struct elf_prstatus, pr_ppid) */
     struct PPCUserRegStruct pr_reg;
-    char pad2[40];
+    char pad3[40]; /* 40 == sizeof(struct elf_prstatus) -
+		            offsetof(struct elf_prstatus, pr_reg) -
+			    sizeof(struct user_pt_regs) */
 } QEMU_PACKED;
 
 
@@ -96,7 +101,7 @@  typedef struct NoteFuncArg {
     DumpState *state;
 } NoteFuncArg;
 
-static void ppc_write_elf_prstatus(NoteFuncArg *arg, PowerPCCPU *cpu)
+static void ppc_write_elf_prstatus(NoteFuncArg *arg, PowerPCCPU *cpu, int id)
 {
     int i;
     reg_t cr;
@@ -109,6 +114,7 @@  static void ppc_write_elf_prstatus(NoteFuncArg *arg, PowerPCCPU *cpu)
 
     prstatus = &note->contents.prstatus;
     memset(prstatus, 0, sizeof(*prstatus));
+    prstatus->pid = cpu_to_dump32(s, id);
     reg = &prstatus->pr_reg;
 
     for (i = 0; i < 32; i++) {
@@ -127,7 +133,7 @@  static void ppc_write_elf_prstatus(NoteFuncArg *arg, PowerPCCPU *cpu)
     reg->ccr = cpu_to_dump_reg(s, cr);
 }
 
-static void ppc_write_elf_fpregset(NoteFuncArg *arg, PowerPCCPU *cpu)
+static void ppc_write_elf_fpregset(NoteFuncArg *arg, PowerPCCPU *cpu, int id)
 {
     int i;
     struct PPCElfFpregset  *fpregset;
@@ -146,7 +152,7 @@  static void ppc_write_elf_fpregset(NoteFuncArg *arg, PowerPCCPU *cpu)
     fpregset->fpscr = cpu_to_dump_reg(s, cpu->env.fpscr);
 }
 
-static void ppc_write_elf_vmxregset(NoteFuncArg *arg, PowerPCCPU *cpu)
+static void ppc_write_elf_vmxregset(NoteFuncArg *arg, PowerPCCPU *cpu, int id)
 {
     int i;
     struct PPCElfVmxregset *vmxregset;
@@ -178,7 +184,7 @@  static void ppc_write_elf_vmxregset(NoteFuncArg *arg, PowerPCCPU *cpu)
     vmxregset->vscr.u32[3] = cpu_to_dump32(s, ppc_get_vscr(&cpu->env));
 }
 
-static void ppc_write_elf_vsxregset(NoteFuncArg *arg, PowerPCCPU *cpu)
+static void ppc_write_elf_vsxregset(NoteFuncArg *arg, PowerPCCPU *cpu, int id)
 {
     int i;
     struct PPCElfVsxregset *vsxregset;
@@ -195,7 +201,7 @@  static void ppc_write_elf_vsxregset(NoteFuncArg *arg, PowerPCCPU *cpu)
     }
 }
 
-static void ppc_write_elf_speregset(NoteFuncArg *arg, PowerPCCPU *cpu)
+static void ppc_write_elf_speregset(NoteFuncArg *arg, PowerPCCPU *cpu, int id)
 {
     struct PPCElfSperegset *speregset;
     Note *note = &arg->note;
@@ -211,7 +217,7 @@  static void ppc_write_elf_speregset(NoteFuncArg *arg, PowerPCCPU *cpu)
 
 static const struct NoteFuncDescStruct {
     int contents_size;
-    void (*note_contents_func)(NoteFuncArg *arg, PowerPCCPU *cpu);
+    void (*note_contents_func)(NoteFuncArg *arg, PowerPCCPU *cpu, int id);
 } note_func[] = {
     {sizeof_field(Note, contents.prstatus),  ppc_write_elf_prstatus},
     {sizeof_field(Note, contents.fpregset),  ppc_write_elf_fpregset},
@@ -282,7 +288,7 @@  static int ppc_write_all_elf_notes(const char *note_name,
         arg.note.hdr.n_descsz = cpu_to_dump32(s, nf->contents_size);
         strncpy(arg.note.name, note_name, sizeof(arg.note.name));
 
-        (*nf->note_contents_func)(&arg, cpu);
+        (*nf->note_contents_func)(&arg, cpu, id);
 
         note_size =
             sizeof(arg.note) - sizeof(arg.note.contents) + nf->contents_size;