On 2022/07/04 14:25, Hari Bathini wrote:
A CPU could be in an emergency stack when it is running in real mode
or any special scenario like TM bad thing. Also, there are dedicated
emergency stacks for machine check and system reset interrupt. Right
now, no backtrace is provided if a CPU is in any of these stacks.
This change ensures backtrace is processed appropriately even when
a CPU is in any one of these emergency stacks. Also, if stack info
cannot be found, print that message always instead of only when
verbose logs are enabled.
Signed-off-by: Hari Bathini <hbathini@xxxxxxxxxxxxx>
---
Changes in v2:
* Avoid using variable length array for paca_ptrs.
defs.h | 12 ++++
ppc64.c | 203 ++++++++++++++++++++++++++++++++++++++++++++++++++++----
2 files changed, 203 insertions(+), 12 deletions(-)
diff --git a/defs.h b/defs.h
index d1d3ea9..9b1b69a 100644
--- a/defs.h
+++ b/defs.h
@@ -6288,6 +6288,13 @@ struct ppc64_elf_prstatus {
#ifdef PPC64
+enum emergency_stack_type {
+ NONE_STACK = 0,
+ EMERGENCY_STACK,
+ NMI_EMERGENCY_STACK,
+ MC_EMERGENCY_STACK
+};
+
struct ppc64_opal {
uint64_t base;
uint64_t entry;
@@ -6307,6 +6314,11 @@ struct machine_specific {
char *hwstackbuf;
uint hwstacksize;
+ /* Emergency stacks */
+ ulong *emergency_sp;
+ ulong *nmi_emergency_sp;
+ ulong *mc_emergency_sp;
+
uint l4_index_size;
uint l3_index_size;
uint l2_index_size;
diff --git a/ppc64.c b/ppc64.c
index 0a3aa5f..8ea91c2 100644
--- a/ppc64.c
+++ b/ppc64.c
@@ -48,6 +48,10 @@ static ulong ppc64_get_stackbase(ulong);
static ulong ppc64_get_stacktop(ulong);
void ppc64_compiler_warning_stub(void);
static ulong ppc64_in_irqstack(ulong);
+static enum emergency_stack_type ppc64_in_emergency_stack(int cpu, ulong addr,
+ bool verbose);
+static void ppc64_set_bt_emergency_stack(enum emergency_stack_type type,
+ struct bt_info *bt);
static char * ppc64_check_eframe(struct ppc64_pt_regs *);
static void ppc64_print_eframe(char *, struct ppc64_pt_regs *,
struct bt_info *);
@@ -56,6 +60,7 @@ static int ppc64_paca_percpu_offset_init(int);
static void ppc64_init_cpu_info(void);
static int ppc64_get_cpu_map(void);
static void ppc64_clear_machdep_cache(void);
+static void ppc64_init_paca_info(void);
static void ppc64_vmemmap_init(void);
static int ppc64_get_kvaddr_ranges(struct vaddr_range *);
static uint get_ptetype(ulong pte);
@@ -692,6 +697,8 @@ ppc64_init(int when)
error(FATAL, "cannot malloc hwirqstack buffer space.");
}
+ ppc64_init_paca_info();
+
if (!machdep->hz) {
machdep->hz = HZ;
if (THIS_KERNEL_VERSION >= LINUX(2,6,0))
@@ -1204,6 +1211,70 @@ ppc64_kvtop(struct task_context *tc, ulong kvaddr,
return ppc64_vtop(kvaddr, (ulong *)vt->kernel_pgd[0], paddr, verbose);
}
+static void
+ppc64_init_paca_info(void)
+{
+ struct machine_specific *ms = machdep->machspec;
+ ulong *paca_ptr;
+ int i;
+
+ if (!(paca_ptrs = (ulong *)calloc(kt->cpus, sizeof(ulong))))
s/paca_ptrs/paca_ptr/
ppc64.c: In function ‘ppc64_init_paca_info’:
ppc64.c:1219:8: error: ‘paca_ptrs’ undeclared (first use in this function); did you mean ‘paca_ptr’?
if (!(paca_ptrs = (ulong *)calloc(kt->cpus, sizeof(ulong))))
^~~~~~~~~
paca_ptr
ppc64.c:1219:8: note: each undeclared identifier is reported only once for each function it appears in
+ error(FATAL, "cannot malloc paca pointers space.\n");
+
+ /* Get paca pointers for all CPUs. */
+ if (symbol_exists("paca_ptrs")) {
+ ulong paca_loc;
+
+ readmem(symbol_value("paca_ptrs"), KVADDR, &paca_loc, sizeof(void *),
+ "paca double pointer", FAULT_ON_ERROR);
+ readmem(paca_loc, KVADDR, paca_ptr, sizeof(void *) * kt->cpus,
+ "paca pointers", FAULT_ON_ERROR);
+ } else if (symbol_exists("paca") &&
+ (get_symbol_type("paca", NULL, NULL) == TYPE_CODE_PTR)) {
+ readmem(symbol_value("paca"), KVADDR, paca_ptr, sizeof(void *) * kt->cpus,
+ "paca pointers", FAULT_ON_ERROR);
+ } else {
+ free(paca_ptrs);
Ditto.
+ return;
+ }
+
+ /* Initialize emergency stacks info. */
+ if (MEMBER_EXISTS("paca_struct", "emergency_sp")) {
+ ulong offset = MEMBER_OFFSET("paca_struct", "emergency_sp");
+
+ if (!(ms->emergency_sp = (ulong *)calloc(kt->cpus, sizeof(ulong))))
+ error(FATAL, "cannot malloc emergency stack space.\n");
+ for (i = 0; i < kt->cpus; i++)
+ readmem(paca_ptr[i] + offset, KVADDR, &ms->emergency_sp[i],
+ sizeof(void *), "paca->emergency_sp",
+ FAULT_ON_ERROR);
+ }
+
+ if (MEMBER_EXISTS("paca_struct", "nmi_emergency_sp")) {
+ ulong offset = MEMBER_OFFSET("paca_struct", "nmi_emergency_sp");
+
+ if (!(ms->nmi_emergency_sp = (ulong *)calloc(kt->cpus, sizeof(ulong))))
+ error(FATAL, "cannot malloc NMI emergency stack space.\n");
+ for (i = 0; i < kt->cpus; i++)
+ readmem(paca_ptr[i] + offset, KVADDR, &ms->nmi_emergency_sp[i],
+ sizeof(void *), "paca->nmi_emergency_sp",
+ FAULT_ON_ERROR);
+ }
+
+ if (MEMBER_EXISTS("paca_struct", "mc_emergency_sp")) {
+ ulong offset = MEMBER_OFFSET("paca_struct", "mc_emergency_sp");
+
+ if (!(ms->mc_emergency_sp = (ulong *)calloc(kt->cpus, sizeof(ulong))))
+ error(FATAL, "cannot malloc machine check emergency stack space.\n");
+ for (i = 0; i < kt->cpus; i++)
+ readmem(paca_ptr[i] + offset, KVADDR, &ms->mc_emergency_sp[i],
+ sizeof(void *), "paca->mc_emergency_sp",
+ FAULT_ON_ERROR);
+ }
+
+ free(paca_ptrs);
Ditto.
But these typos can be fixed when merging, no need to respin for this.
