From e82a3b75127188f20c7780bec580e148beb29da7 Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Tue, 16 Jun 2009 20:51:48 +0000 Subject: parisc: ensure broadcast tlb purge runs single threaded The TLB flushing functions on hppa, which causes PxTLB broadcasts on the system bus, needs to be protected by irq-safe spinlocks to avoid irq handlers to deadlock the kernel. The deadlocks only happened during I/O intensive loads and triggered pretty seldom, which is why this bug went so long unnoticed. Signed-off-by: Helge Deller [edited to use spin_lock_irqsave on UP as well since we'd been locking there all this time anyway, --kyle] Signed-off-by: Kyle McMartin --- arch/parisc/kernel/pci-dma.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'arch/parisc/kernel/pci-dma.c') diff --git a/arch/parisc/kernel/pci-dma.c b/arch/parisc/kernel/pci-dma.c index 7d927eac932b..c07f618ff7da 100644 --- a/arch/parisc/kernel/pci-dma.c +++ b/arch/parisc/kernel/pci-dma.c @@ -90,12 +90,14 @@ static inline int map_pte_uncached(pte_t * pte, if (end > PMD_SIZE) end = PMD_SIZE; do { + unsigned long flags; + if (!pte_none(*pte)) printk(KERN_ERR "map_pte_uncached: page already exists\n"); set_pte(pte, __mk_pte(*paddr_ptr, PAGE_KERNEL_UNC)); - purge_tlb_start(); + purge_tlb_start(flags); pdtlb_kernel(orig_vaddr); - purge_tlb_end(); + purge_tlb_end(flags); vaddr += PAGE_SIZE; orig_vaddr += PAGE_SIZE; (*paddr_ptr) += PAGE_SIZE; @@ -168,11 +170,13 @@ static inline void unmap_uncached_pte(pmd_t * pmd, unsigned long vaddr, if (end > PMD_SIZE) end = PMD_SIZE; do { + unsigned long flags; pte_t page = *pte; + pte_clear(&init_mm, vaddr, pte); - purge_tlb_start(); + purge_tlb_start(flags); pdtlb_kernel(orig_vaddr); - purge_tlb_end(); + purge_tlb_end(flags); vaddr += PAGE_SIZE; orig_vaddr += PAGE_SIZE; pte++; -- cgit v1.2.1