ARM: 6052/1: kdump: make kexec work in interrupt context

When crash happens in interrupt context there is no userspace context.
We always use current->active_mm in those cases.

Signed-off-by: Mika Westerberg <ext-mika.1.westerberg@nokia.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 6 insertions, 4 deletions

diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index 4223d086aa17..241c24a1c18f 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -1054,10 +1054,12 @@ void setup_mm_for_reboot(char mode)
         pgd_t *pgd;
         int i;
 
-        if (current->mm && current->mm->pgd)
-                pgd = current->mm->pgd;
-        else
-                pgd = init_mm.pgd;
+        /*
+         * We need to access to user-mode page tables here. For kernel threads
+         * we don't have any user-mode mappings so we use the context that we
+         * "borrowed".
+         */
+        pgd = current->active_mm->pgd;
 
         base_pmdval = PMD_SECT_AP_WRITE | PMD_SECT_AP_READ | PMD_TYPE_SECT;
         if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale())