This is a note to let you know that I've just added the patch titled
MIPS: Stack unwinding while on IRQ stack
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mips-stack-unwinding-while-on-irq-stack.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From d42d8d106b0275b027c1e8992c42aecf933436ea Mon Sep 17 00:00:00 2001
From: Matt Redfearn <matt.redfearn@xxxxxxxxxx>
Date: Mon, 19 Dec 2016 14:20:57 +0000
Subject: MIPS: Stack unwinding while on IRQ stack
From: Matt Redfearn <matt.redfearn@xxxxxxxxxx>
commit d42d8d106b0275b027c1e8992c42aecf933436ea upstream.
Within unwind stack, check if the stack pointer being unwound is within
the CPU's irq_stack and if so use that page rather than the task's stack
page.
Signed-off-by: Matt Redfearn <matt.redfearn@xxxxxxxxxx>
Acked-by: Jason A. Donenfeld <jason@xxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Adam Buchbinder <adam.buchbinder@xxxxxxxxx>
Cc: Maciej W. Rozycki <macro@xxxxxxxxxx>
Cc: Marcin Nowakowski <marcin.nowakowski@xxxxxxxxxx>
Cc: Chris Metcalf <cmetcalf@xxxxxxxxxxxx>
Cc: James Hogan <james.hogan@xxxxxxxxxx>
Cc: Paul Burton <paul.burton@xxxxxxxxxx>
Cc: Jiri Slaby <jslaby@xxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Patchwork: https://patchwork.linux-mips.org/patch/14741/
Signed-off-by: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Signed-off-by: Amit Pundir <amit.pundir@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/mips/kernel/process.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -32,6 +32,7 @@
#include <asm/cpu.h>
#include <asm/dsp.h>
#include <asm/fpu.h>
+#include <asm/irq.h>
#include <asm/msa.h>
#include <asm/pgtable.h>
#include <asm/mipsregs.h>
@@ -552,7 +553,19 @@ EXPORT_SYMBOL(unwind_stack_by_address);
unsigned long unwind_stack(struct task_struct *task, unsigned long *sp,
unsigned long pc, unsigned long *ra)
{
- unsigned long stack_page = (unsigned long)task_stack_page(task);
+ unsigned long stack_page = 0;
+ int cpu;
+
+ for_each_possible_cpu(cpu) {
+ if (on_irq_stack(cpu, *sp)) {
+ stack_page = (unsigned long)irq_stack[cpu];
+ break;
+ }
+ }
+
+ if (!stack_page)
+ stack_page = (unsigned long)task_stack_page(task);
+
return unwind_stack_by_address(stack_page, sp, pc, ra);
}
#endif
Patches currently in stable-queue which might be from matt.redfearn@xxxxxxxxxx are
queue-4.4/mips-only-change-28-to-thread_info-if-coming-from-user-mode.patch
queue-4.4/mips-stack-unwinding-while-on-irq-stack.patch
queue-4.4/mips-introduce-irq_stack.patch