From: Helge Deller deller@gmx.de
commit 61e150fb310729c98227a5edf6e4a3619edc3702 upstream.
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 parisc 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: linux-parisc@vger.kernel.org Cc: stable@kernel.org # 5.18+ Signed-off-by: Helge Deller deller@gmx.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/parisc/include/asm/cacheflush.h | 4 ++++ arch/parisc/kernel/cache.c | 5 +++-- 2 files changed, 7 insertions(+), 2 deletions(-)
--- a/arch/parisc/include/asm/cacheflush.h +++ b/arch/parisc/include/asm/cacheflush.h @@ -48,6 +48,10 @@ void flush_dcache_page(struct page *page
#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)
#define flush_icache_page(vma,page) do { \ flush_kernel_dcache_page_addr(page_address(page)); \ --- a/arch/parisc/kernel/cache.c +++ b/arch/parisc/kernel/cache.c @@ -399,6 +399,7 @@ void flush_dcache_page(struct page *page unsigned long offset; unsigned long addr, old_addr = 0; unsigned long count = 0; + unsigned long flags; pgoff_t pgoff;
if (mapping && !mapping_mapped(mapping)) { @@ -420,7 +421,7 @@ void flush_dcache_page(struct page *page * to flush one address here for them all to become coherent * on machines that support equivalent aliasing */ - flush_dcache_mmap_lock(mapping); + flush_dcache_mmap_lock_irqsave(mapping, flags); vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) { offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT; addr = mpnt->vm_start + offset; @@ -460,7 +461,7 @@ void flush_dcache_page(struct page *page } WARN_ON(++count == 4096); } - flush_dcache_mmap_unlock(mapping); + flush_dcache_mmap_unlock_irqrestore(mapping, flags); } EXPORT_SYMBOL(flush_dcache_page);