From 0d1d365d1d4423b55e3a18e1d1ad2036aa1708ea Mon Sep 17 00:00:00 2001 From: Paul Burton Date: Fri, 25 Nov 2016 18:46:09 +0000 Subject: [PATCH] MIPS: WARN_ON invalid DMA cache maintenance, not BUG_ON [ Upstream commit d4da0e97baea8768b3d66ccef3967bebd50dfc3b ] If a driver causes DMA cache maintenance with a zero length then we currently BUG and kill the kernel. As this is a scenario that we may well be able to recover from, WARN & return in the condition instead. Signed-off-by: Paul Burton Acked-by: Florian Fainelli Patchwork: https://patchwork.linux-mips.org/patch/14623/ Cc: Ralf Baechle Cc: linux-mips@linux-mips.org Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- arch/mips/mm/c-r4k.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/mips/mm/c-r4k.c b/arch/mips/mm/c-r4k.c index e12dfa48b478..a5893b2cdc0e 100644 --- a/arch/mips/mm/c-r4k.c +++ b/arch/mips/mm/c-r4k.c @@ -835,7 +835,8 @@ static void r4k_flush_icache_user_range(unsigned long start, unsigned long end) static void r4k_dma_cache_wback_inv(unsigned long addr, unsigned long size) { /* Catch bad driver code */ - BUG_ON(size == 0); + if (WARN_ON(size == 0)) + return; preempt_disable(); if (cpu_has_inclusive_pcaches) { @@ -871,7 +872,8 @@ static void r4k_dma_cache_wback_inv(unsigned long addr, unsigned long size) static void r4k_dma_cache_inv(unsigned long addr, unsigned long size) { /* Catch bad driver code */ - BUG_ON(size == 0); + if (WARN_ON(size == 0)) + return; preempt_disable(); if (cpu_has_inclusive_pcaches) {