diff options
| author | Thomas Gleixner <[email protected]> | 2019-04-14 17:59:51 +0200 |
|---|---|---|
| committer | Borislav Petkov <[email protected]> | 2019-04-17 13:02:48 +0200 |
| commit | bf5882abab773afd1277415e2f826b21de28f30d (patch) | |
| tree | 8267fab244b0ed024482d8568e4f56d386ebd836 | |
| parent | d876b67343a648f3613506c7dbfed088fa0c875b (diff) | |
x86/irq/64: Use cpu entry area instead of orig_ist
The orig_ist[] array is a shadow copy of the IST array in the TSS. The
reason why it exists is that older kernels used two TSS variants with
different pointers into the debug stack. orig_ist[] contains the real
starting points.
There is no point anymore to do so because the same information can be
retrieved using the base address of the cpu entry area mapping and the
offsets of the various exception stacks.
No functional change. Preparation for removing orig_ist.
Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Borislav Petkov <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Nicolai Stange <[email protected]>
Cc: Sean Christopherson <[email protected]>
Cc: x86-ml <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
| -rw-r--r-- | arch/x86/kernel/irq_64.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c index 182e8b245e06..7eb6f8d11bfd 100644 --- a/arch/x86/kernel/irq_64.c +++ b/arch/x86/kernel/irq_64.c @@ -18,6 +18,8 @@ #include <linux/uaccess.h> #include <linux/smp.h> #include <linux/sched/task_stack.h> + +#include <asm/cpu_entry_area.h> #include <asm/io_apic.h> #include <asm/apic.h> @@ -43,10 +45,9 @@ static inline void stack_overflow_check(struct pt_regs *regs) { #ifdef CONFIG_DEBUG_STACKOVERFLOW #define STACK_MARGIN 128 - struct orig_ist *oist; - u64 irq_stack_top, irq_stack_bottom; - u64 estack_top, estack_bottom; + u64 irq_stack_top, irq_stack_bottom, estack_top, estack_bottom; u64 curbase = (u64)task_stack_page(current); + struct cea_exception_stacks *estacks; if (user_mode(regs)) return; @@ -60,9 +61,9 @@ static inline void stack_overflow_check(struct pt_regs *regs) if (regs->sp >= irq_stack_bottom && regs->sp <= irq_stack_top) return; - oist = this_cpu_ptr(&orig_ist); - estack_top = (u64)oist->ist[ESTACK_DB]; - estack_bottom = estack_top - DEBUG_STKSZ + STACK_MARGIN; + estacks = __this_cpu_read(cea_exception_stacks); + estack_top = CEA_ESTACK_TOP(estacks, DB); + estack_bottom = CEA_ESTACK_BOT(estacks, DB) + STACK_MARGIN; if (regs->sp >= estack_bottom && regs->sp <= estack_top) return; |