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Groups > linux.kernel > #1448190
| From | Josh Poimboeuf <jpoimboe@redhat.com> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | [PATCH 07/19] x86/dumpstack: add IRQ_USABLE_STACK_SIZE define |
| Date | 2016-07-21 23:30 +0200 |
| Message-ID | <rXtHB-4Eb-57@gated-at.bofh.it> (permalink) |
| References | <rXtHz-4Eb-5@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
For reasons unknown, the x86_64 irq stack starts at an offset 64 bytes
from the end of the page. At least make that explicit.
FIXME: Can we just remove the 64 byte gap? If not, at least document
why.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
---
arch/x86/include/asm/page_64_types.h | 19 +++++++++++--------
arch/x86/kernel/cpu/common.c | 2 +-
arch/x86/kernel/dumpstack_64.c | 8 +++-----
arch/x86/kernel/setup_percpu.c | 2 +-
4 files changed, 16 insertions(+), 15 deletions(-)
diff --git a/arch/x86/include/asm/page_64_types.h b/arch/x86/include/asm/page_64_types.h
index 9215e05..6256baf 100644
--- a/arch/x86/include/asm/page_64_types.h
+++ b/arch/x86/include/asm/page_64_types.h
@@ -12,17 +12,20 @@
#endif
#define THREAD_SIZE_ORDER (2 + KASAN_STACK_ORDER)
-#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
-#define CURRENT_MASK (~(THREAD_SIZE - 1))
+#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
+#define CURRENT_MASK (~(THREAD_SIZE - 1))
-#define EXCEPTION_STACK_ORDER (0 + KASAN_STACK_ORDER)
-#define EXCEPTION_STKSZ (PAGE_SIZE << EXCEPTION_STACK_ORDER)
+#define EXCEPTION_STACK_ORDER (0 + KASAN_STACK_ORDER)
+#define EXCEPTION_STKSZ (PAGE_SIZE << EXCEPTION_STACK_ORDER)
-#define DEBUG_STACK_ORDER (EXCEPTION_STACK_ORDER + 1)
-#define DEBUG_STKSZ (PAGE_SIZE << DEBUG_STACK_ORDER)
+#define DEBUG_STACK_ORDER (EXCEPTION_STACK_ORDER + 1)
+#define DEBUG_STKSZ (PAGE_SIZE << DEBUG_STACK_ORDER)
-#define IRQ_STACK_ORDER (2 + KASAN_STACK_ORDER)
-#define IRQ_STACK_SIZE (PAGE_SIZE << IRQ_STACK_ORDER)
+#define IRQ_STACK_ORDER (2 + KASAN_STACK_ORDER)
+#define IRQ_STACK_SIZE (PAGE_SIZE << IRQ_STACK_ORDER)
+
+/* FIXME: why? */
+#define IRQ_USABLE_STACK_SIZE (IRQ_STACK_SIZE - 64)
#define DOUBLEFAULT_STACK 1
#define NMI_STACK 2
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 809eda0..8f3f7a4 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1281,7 +1281,7 @@ DEFINE_PER_CPU(struct task_struct *, current_task) ____cacheline_aligned =
EXPORT_PER_CPU_SYMBOL(current_task);
DEFINE_PER_CPU(char *, irq_stack_ptr) =
- init_per_cpu_var(irq_stack_union.irq_stack) + IRQ_STACK_SIZE - 64;
+ init_per_cpu_var(irq_stack_union.irq_stack) + IRQ_USABLE_STACK_SIZE;
DEFINE_PER_CPU(unsigned int, irq_count) __visible = -1;
diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c
index 55cc88f..6a2d14e 100644
--- a/arch/x86/kernel/dumpstack_64.c
+++ b/arch/x86/kernel/dumpstack_64.c
@@ -103,9 +103,6 @@ in_irq_stack(unsigned long *stack, unsigned long *irq_stack,
return (stack >= irq_stack && stack < irq_stack_end);
}
-static const unsigned long irq_stack_size =
- (IRQ_STACK_SIZE - 64) / sizeof(unsigned long);
-
enum stack_type {
STACK_IS_UNKNOWN,
STACK_IS_NORMAL,
@@ -133,7 +130,7 @@ analyze_stack(int cpu, struct task_struct *task, unsigned long *stack,
return STACK_IS_NORMAL;
*stack_end = irq_stack;
- irq_stack = irq_stack - irq_stack_size;
+ irq_stack -= (IRQ_USABLE_STACK_SIZE / sizeof(long));
if (in_irq_stack(stack, irq_stack, *stack_end))
return STACK_IS_IRQ;
@@ -246,7 +243,8 @@ show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
cpu = smp_processor_id();
irq_stack_end = (unsigned long *)(per_cpu(irq_stack_ptr, cpu));
- irq_stack = (unsigned long *)(per_cpu(irq_stack_ptr, cpu) - IRQ_STACK_SIZE);
+ irq_stack = (unsigned long *)(per_cpu(irq_stack_ptr, cpu) -
+ IRQ_USABLE_STACK_SIZE);
sp = sp ? : get_stack_pointer(task, regs);
diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c
index e4fcb87..043454f 100644
--- a/arch/x86/kernel/setup_percpu.c
+++ b/arch/x86/kernel/setup_percpu.c
@@ -244,7 +244,7 @@ void __init setup_per_cpu_areas(void)
#ifdef CONFIG_X86_64
per_cpu(irq_stack_ptr, cpu) =
per_cpu(irq_stack_union.irq_stack, cpu) +
- IRQ_STACK_SIZE - 64;
+ IRQ_USABLE_STACK_SIZE;
#endif
#ifdef CONFIG_NUMA
per_cpu(x86_cpu_to_node_map, cpu) =
--
2.7.4
Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
[PATCH 00/19] x86/dumpstack: rewrite x86 stack dump code Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-21 23:30 +0200
[PATCH 05/19] x86/dumpstack: fix function graph tracing stack dump reliability issues Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-21 23:30 +0200
[PATCH 04/19] x86/dumpstack: make printk_stack_address() more generally useful Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-21 23:30 +0200
[PATCH 18/19] x86/dumpstack: print stack identifier on its own line Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-21 23:30 +0200
[PATCH 13/19] x86/stacktrace: convert save_stack_trace_*() to the new unwinder Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-21 23:30 +0200
[PATCH 19/19] x86/dumpstack: print any pt_regs found on the stack Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-21 23:30 +0200
Re: [PATCH 19/19] x86/dumpstack: print any pt_regs found on the stack Andy Lutomirski <luto@amacapital.net> - 2016-07-22 00:40 +0200
Re: [PATCH 19/19] x86/dumpstack: print any pt_regs found on the stack Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-22 05:40 +0200
Re: [PATCH 19/19] x86/dumpstack: print any pt_regs found on the stack Andy Lutomirski <luto@amacapital.net> - 2016-07-22 07:20 +0200
Re: [PATCH 19/19] x86/dumpstack: print any pt_regs found on the stack Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-22 18:00 +0200
Re: [PATCH 19/19] x86/dumpstack: print any pt_regs found on the stack Andy Lutomirski <luto@amacapital.net> - 2016-07-22 23:50 +0200
Re: [PATCH 19/19] x86/dumpstack: print any pt_regs found on the stack Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-23 00:30 +0200
Re: [PATCH 19/19] x86/dumpstack: print any pt_regs found on the stack Andy Lutomirski <luto@amacapital.net> - 2016-07-23 01:20 +0200
Re: [PATCH 19/19] x86/dumpstack: print any pt_regs found on the stack Andy Lutomirski <luto@amacapital.net> - 2016-07-23 01:40 +0200
Re: [PATCH 19/19] x86/dumpstack: print any pt_regs found on the stack Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-23 02:10 +0200
Re: [PATCH 19/19] x86/dumpstack: print any pt_regs found on the stack Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-23 01:40 +0200
[PATCH 08/19] x86/dumpstack: don't disable preemption in show_stack_log_lvl() and dump_trace() Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-21 23:30 +0200
[PATCH 14/19] oprofile/x86: convert x86_backtrace() to the new unwinder Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-21 23:30 +0200
[PATCH 06/19] x86/dumpstack: remove extra brackets around "EOE" Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-21 23:30 +0200
[PATCH 10/19] x86/dumpstack: add get_stack_info() interface Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-21 23:30 +0200
Re: [PATCH 10/19] x86/dumpstack: add get_stack_info() interface Andy Lutomirski <luto@amacapital.net> - 2016-07-23 01:30 +0200
Re: [PATCH 10/19] x86/dumpstack: add get_stack_info() interface Andy Lutomirski <luto@amacapital.net> - 2016-07-23 02:00 +0200
Re: [PATCH 10/19] x86/dumpstack: add get_stack_info() interface Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-23 15:10 +0200
Re: [PATCH 10/19] x86/dumpstack: add get_stack_info() interface Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-23 02:00 +0200
Re: [PATCH 10/19] x86/dumpstack: add get_stack_info() interface Andy Lutomirski <luto@amacapital.net> - 2016-07-23 02:20 +0200
Re: [PATCH 10/19] x86/dumpstack: add get_stack_info() interface Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-23 16:10 +0200
[PATCH 01/19] x86/dumpstack: remove show_trace() Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-21 23:30 +0200
Re: [PATCH 01/19] x86/dumpstack: remove show_trace() Andy Lutomirski <luto@amacapital.net> - 2016-07-22 00:00 +0200
[PATCH 12/19] perf/x86: convert perf_callchain_kernel() to the new unwinder Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-21 23:30 +0200
[PATCH 02/19] x86/dumpstack: add get_stack_pointer() and get_frame_pointer() Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-21 23:30 +0200
Re: [PATCH 02/19] x86/dumpstack: add get_stack_pointer() and get_frame_pointer() Andy Lutomirski <luto@amacapital.net> - 2016-07-22 00:00 +0200
[PATCH 11/19] x86/dumptrace: add new unwind interface and implementations Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-21 23:30 +0200
[PATCH 09/19] x86/dumpstack: simplify in_exception_stack() Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-21 23:30 +0200
Re: [PATCH 09/19] x86/dumpstack: simplify in_exception_stack() Andy Lutomirski <luto@amacapital.net> - 2016-07-22 00:10 +0200
[PATCH 07/19] x86/dumpstack: add IRQ_USABLE_STACK_SIZE define Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-21 23:30 +0200
Re: [PATCH 07/19] x86/dumpstack: add IRQ_USABLE_STACK_SIZE define Andy Lutomirski <luto@amacapital.net> - 2016-07-22 00:10 +0200
Re: [PATCH 07/19] x86/dumpstack: add IRQ_USABLE_STACK_SIZE define Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-22 03:50 +0200
Re: [PATCH 07/19] x86/dumpstack: add IRQ_USABLE_STACK_SIZE define Ingo Molnar <mingo@kernel.org> - 2016-07-22 10:30 +0200
Re: [PATCH 00/19] x86/dumpstack: rewrite x86 stack dump code Linus Torvalds <torvalds@linux-foundation.org> - 2016-07-23 02:30 +0200
Re: [PATCH 00/19] x86/dumpstack: rewrite x86 stack dump code Andy Lutomirski <luto@amacapital.net> - 2016-07-23 02:40 +0200
Re: [PATCH 00/19] x86/dumpstack: rewrite x86 stack dump code Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-23 07:40 +0200
Re: [PATCH 00/19] x86/dumpstack: rewrite x86 stack dump code Linus Torvalds <torvalds@linux-foundation.org> - 2016-07-23 07:50 +0200
Re: [PATCH 00/19] x86/dumpstack: rewrite x86 stack dump code Josh Poimboeuf <jpoimboe@redhat.com> - 2016-07-23 15:00 +0200
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