From f1b346fdb72c86367c28e79d140ccc8515a0c3f4 Mon Sep 17 00:00:00 2001 From: Julien Grall Date: Mon, 18 Nov 2013 13:08:23 +0000 Subject: [PATCH] xen/arm: ioremap_attr: return NULL is __vmap failed Most of ioremap_* caller check if ioremap returns NULL. Actually, if the physical address is non-aligned, Xen will return the pointer given by __vmap plus the offset in the page. So if ioremap_* fails, the caller will retrieve an non-NULL address and continue as if there was no error. Signed-off-by: Julien Grall Acked-by: Stefano Stabellini Acked-by: Ian Campbell --- xen/arch/arm/mm.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c index 123280e826..2de7dc7d0f 100644 --- a/xen/arch/arm/mm.c +++ b/xen/arch/arm/mm.c @@ -742,8 +742,12 @@ void *ioremap_attr(paddr_t pa, size_t len, unsigned int attributes) unsigned long pfn = PFN_DOWN(pa); unsigned int offs = pa & (PAGE_SIZE - 1); unsigned int nr = PFN_UP(offs + len); + void *ptr = __vmap(&pfn, nr, 1, 1, attributes); - return (__vmap(&pfn, nr, 1, 1, attributes) + offs); + if ( ptr == NULL ) + return NULL; + + return ptr + offs; } void *ioremap(paddr_t pa, size_t len) -- 2.30.2