Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c
index 5cdb9e8..87b9789 100644
--- a/arch/x86/kernel/dumpstack_64.c
+++ b/arch/x86/kernel/dumpstack_64.c
@@ -16,23 +16,21 @@
#include <linux/bug.h>
#include <linux/nmi.h>
+#include <asm/cpu_entry_area.h>
#include <asm/stacktrace.h>
-static char *exception_stack_names[N_EXCEPTION_STACKS] = {
- [ DOUBLEFAULT_STACK-1 ] = "#DF",
- [ NMI_STACK-1 ] = "NMI",
- [ DEBUG_STACK-1 ] = "#DB",
- [ MCE_STACK-1 ] = "#MC",
-};
-
-static unsigned long exception_stack_sizes[N_EXCEPTION_STACKS] = {
- [0 ... N_EXCEPTION_STACKS - 1] = EXCEPTION_STKSZ,
- [DEBUG_STACK - 1] = DEBUG_STKSZ
+static const char * const exception_stack_names[] = {
+ [ ESTACK_DF ] = "#DF",
+ [ ESTACK_NMI ] = "NMI",
+ [ ESTACK_DB2 ] = "#DB2",
+ [ ESTACK_DB1 ] = "#DB1",
+ [ ESTACK_DB ] = "#DB",
+ [ ESTACK_MCE ] = "#MC",
};
const char *stack_type_name(enum stack_type type)
{
- BUILD_BUG_ON(N_EXCEPTION_STACKS != 4);
+ BUILD_BUG_ON(N_EXCEPTION_STACKS != 6);
if (type == STACK_TYPE_IRQ)
return "IRQ";
@@ -52,43 +50,91 @@
return NULL;
}
+/**
+ * struct estack_pages - Page descriptor for exception stacks
+ * @offs: Offset from the start of the exception stack area
+ * @size: Size of the exception stack
+ * @type: Type to store in the stack_info struct
+ */
+struct estack_pages {
+ u32 offs;
+ u16 size;
+ u16 type;
+};
+
+#define EPAGERANGE(st) \
+ [PFN_DOWN(CEA_ESTACK_OFFS(st)) ... \
+ PFN_DOWN(CEA_ESTACK_OFFS(st) + CEA_ESTACK_SIZE(st) - 1)] = { \
+ .offs = CEA_ESTACK_OFFS(st), \
+ .size = CEA_ESTACK_SIZE(st), \
+ .type = STACK_TYPE_EXCEPTION + ESTACK_ ##st, }
+
+/*
+ * Array of exception stack page descriptors. If the stack is larger than
+ * PAGE_SIZE, all pages covering a particular stack will have the same
+ * info. The guard pages including the not mapped DB2 stack are zeroed
+ * out.
+ */
+static const
+struct estack_pages estack_pages[CEA_ESTACK_PAGES] ____cacheline_aligned = {
+ EPAGERANGE(DF),
+ EPAGERANGE(NMI),
+ EPAGERANGE(DB1),
+ EPAGERANGE(DB),
+ EPAGERANGE(MCE),
+};
+
static bool in_exception_stack(unsigned long *stack, struct stack_info *info)
{
- unsigned long *begin, *end;
+ unsigned long begin, end, stk = (unsigned long)stack;
+ const struct estack_pages *ep;
struct pt_regs *regs;
- unsigned k;
+ unsigned int k;
- BUILD_BUG_ON(N_EXCEPTION_STACKS != 4);
+ BUILD_BUG_ON(N_EXCEPTION_STACKS != 6);
- for (k = 0; k < N_EXCEPTION_STACKS; k++) {
- end = (unsigned long *)raw_cpu_ptr(&orig_ist)->ist[k];
- begin = end - (exception_stack_sizes[k] / sizeof(long));
- regs = (struct pt_regs *)end - 1;
+ begin = (unsigned long)__this_cpu_read(cea_exception_stacks);
+ /*
+ * Handle the case where stack trace is collected _before_
+ * cea_exception_stacks had been initialized.
+ */
+ if (!begin)
+ return false;
- if (stack <= begin || stack >= end)
- continue;
+ end = begin + sizeof(struct cea_exception_stacks);
+ /* Bail if @stack is outside the exception stack area. */
+ if (stk < begin || stk >= end)
+ return false;
- info->type = STACK_TYPE_EXCEPTION + k;
- info->begin = begin;
- info->end = end;
- info->next_sp = (unsigned long *)regs->sp;
+ /* Calc page offset from start of exception stacks */
+ k = (stk - begin) >> PAGE_SHIFT;
+ /* Lookup the page descriptor */
+ ep = &estack_pages[k];
+ /* Guard page? */
+ if (!ep->size)
+ return false;
- return true;
- }
+ begin += (unsigned long)ep->offs;
+ end = begin + (unsigned long)ep->size;
+ regs = (struct pt_regs *)end - 1;
- return false;
+ info->type = ep->type;
+ info->begin = (unsigned long *)begin;
+ info->end = (unsigned long *)end;
+ info->next_sp = (unsigned long *)regs->sp;
+ return true;
}
static bool in_irq_stack(unsigned long *stack, struct stack_info *info)
{
- unsigned long *end = (unsigned long *)this_cpu_read(irq_stack_ptr);
+ unsigned long *end = (unsigned long *)this_cpu_read(hardirq_stack_ptr);
unsigned long *begin = end - (IRQ_STACK_SIZE / sizeof(long));
/*
* This is a software stack, so 'end' can be a valid stack pointer.
* It just means the stack is empty.
*/
- if (stack <= begin || stack > end)
+ if (stack < begin || stack >= end)
return false;
info->type = STACK_TYPE_IRQ;