| From foo@baz Mon Sep 17 12:33:31 CEST 2018 |
| From: Paul Burton <paul.burton@imgtec.com> |
| Date: Fri, 25 Nov 2016 18:46:09 +0000 |
| Subject: MIPS: WARN_ON invalid DMA cache maintenance, not BUG_ON |
| |
| From: Paul Burton <paul.burton@imgtec.com> |
| |
| [ 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 <paul.burton@mips.com> |
| Acked-by: Florian Fainelli <f.fainelli@gmail.com> |
| Patchwork: https://patchwork.linux-mips.org/patch/14623/ |
| Cc: Ralf Baechle <ralf@linux-mips.org> |
| Cc: linux-mips@linux-mips.org |
| Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| arch/mips/mm/c-r4k.c | 6 ++++-- |
| 1 file changed, 4 insertions(+), 2 deletions(-) |
| |
| --- 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( |
| 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(unsi |
| 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) { |
