From: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> commit 88d7b12068b95731c280af8ce88e8ee9561f96de upstream. We already round down the address in kunmap_local_indexed() which is the other implementation of __kunmap_local(). The only implementation of kunmap_flush_on_unmap() is PA-RISC which is expecting a page-aligned address. This may be causing PA-RISC to be flushing the wrong addresses currently. Link: https://lkml.kernel.org/r/20230126200727.1680362-1-willy@xxxxxxxxxxxxx Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Fixes: 298fa1ad5571 ("highmem: Provide generic variant of kmap_atomic*") Reviewed-by: Ira Weiny <ira.weiny@xxxxxxxxx> Cc: "Fabio M. De Francesco" <fmdefrancesco@xxxxxxxxx> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Helge Deller <deller@xxxxxx> Cc: Alexander Potapenko <glider@xxxxxxxxxx> Cc: Andrey Konovalov <andreyknvl@xxxxxxxxx> Cc: Bagas Sanjaya <bagasdotme@xxxxxxxxx> Cc: David Sterba <dsterba@xxxxxxxx> Cc: Kees Cook <keescook@xxxxxxxxxxxx> Cc: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Cc: Tony Luck <tony.luck@xxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- include/linux/highmem-internal.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/include/linux/highmem-internal.h +++ b/include/linux/highmem-internal.h @@ -184,7 +184,7 @@ static inline void *kmap_local_pfn(unsig static inline void __kunmap_local(void *addr) { #ifdef ARCH_HAS_FLUSH_ON_KUNMAP - kunmap_flush_on_unmap(addr); + kunmap_flush_on_unmap(PTR_ALIGN_DOWN(addr, PAGE_SIZE)); #endif } @@ -211,7 +211,7 @@ static inline void *kmap_atomic_pfn(unsi static inline void __kunmap_atomic(void *addr) { #ifdef ARCH_HAS_FLUSH_ON_KUNMAP - kunmap_flush_on_unmap(addr); + kunmap_flush_on_unmap(PTR_ALIGN_DOWN(addr, PAGE_SIZE)); #endif pagefault_enable(); if (IS_ENABLED(CONFIG_PREEMPT_RT))
