xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

[SPARC64]: Bulletproof MMU context locking.

Browse Source 
1) Always spin_lock_init() in init_context().  The caller essentially
   clears it out, or copies the mm info from the parent.  In both
   cases we need to explicitly initialize the spinlock.

2) Always do explicit IRQ disabling while taking mm->context.lock
   and ctx_alloc_lock.

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller
2006-03-06 19:59:50 -08:00
parent 9132983ae1
commit a77754b4d0
3 changed files with 7 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
include/asm-sparc64/mmu_context.h
View File

@@ -67,14 +67,14 @@ extern void __flush_tlb_mm(unsigned long, unsigned long);
/* Switch the current MM context. Interrupts are disabled. */
static inline void switch_mm(struct mm_struct *old_mm, struct mm_struct *mm, struct task_struct *tsk)
{
unsigned long ctx_valid;
unsigned long ctx_valid, flags;
int cpu;
spin_lock(&mm->context.lock);
spin_lock_irqsave(&mm->context.lock, flags);
ctx_valid = CTX_VALID(mm->context);
if (!ctx_valid)
get_new_mmu_context(mm);
spin_unlock(&mm->context.lock);
spin_unlock_irqrestore(&mm->context.lock, flags);
if (!ctx_valid || (old_mm != mm)) {
load_secondary_context(mm);