nios2: Fix flush_dcache_page() for usage from irq context
PATCH v2 1/1 nios2: Fix flush_dcache_page() for usage from irq context
Since at least kernel 6.1, flush_dcache_page() is called with IRQs disabled, e.g. from aio_complete().
But the current implementation for flush_dcache_page() on NIOS2 unintentionally re-enables IRQs, which may lead to deadlocks.
Fix it by using xa_lock_irqsave() and xa_unlock_irqrestore() for the flush_dcache_mmap_*lock() macros instead.
Cc Dinh Nguyen <[email protected]>
Signed-off-by Helge Deller <[email protected]>
---
v2:
- rebased patch on top of for-next series, to be applied after the folio patches
---
arch/nios2/include/asm/cacheflush.h +4 -0
@@ -52,5 +52,9 @@ extern void invalidate_dcache_range(unsigned long start, unsigned long end);#define flush_dcache_mmap_lock (mapping) xa_lock_irq(&mapping->i_pages)#define flush_dcache_mmap_unlock (mapping) xa_unlock_irq(&mapping->i_pages) +#define flush_dcache_mmap_lock_irqsave (mapping, flags) \ + xa_lock_irqsave(&mapping->i_pages, flags) +#define flush_dcache_mmap_unlock_irqrestore (mapping, flags) \ + xa_unlock_irqrestore(&mapping->i_pages, flags)#endif /* _ASM_NIOS2_CACHEFLUSH_H */
arch/nios2/mm/cacheflush.c +3 -2
@@ -75,12 +75,13 @@ static void flush_aliases(struct address_space *mapping, struct folio *folio) {struct mm_struct *mm = current->active_mm;struct vm_area_struct *vma; +unsigned long flags;pgoff_t pgoff;unsigned long nr =folio_nr_pages (folio); pgoff = folio->index; -flush_dcache_mmap_lock (mapping); +flush_dcache_mmap_lock_irqsave (mapping, flags); vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff + nr - 1) {unsigned long start;
@@ -92,7 +93,7 @@ static void flush_aliases(struct address_space *mapping, struct folio *folio) start = vma->vm_start + ((pgoff - vma->vm_pgoff) <<PAGE_SHIFT );flush_cache_range (vma, start, start + nr *PAGE_SIZE ); } -flush_dcache_mmap_unlock (mapping); +flush_dcache_mmap_unlock_irqrestore (mapping, flags); }void flush_cache_all (void )