[PATCH] powerpc/pmem: Fix kernel crash due to wrong range value usage in flush_dcache_range

Sachin Sant sachinp at linux.vnet.ibm.com
Thu Dec 5 00:48:41 AEDT 2019


> 
> Fixes: 076265907cf9 ("powerpc: Chunk calls to flush_dcache_range in arch_*_memory")
> Reported-by: Sachin Sant <sachinp at linux.vnet.ibm.com>
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar at linux.ibm.com>
> ---
> arch/powerpc/mm/mem.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
> 

It took a while to setup environment on a replacement machine. 
Was able to test the fix. With this fix applied I no longer see the problem.

Tested-by: Sachin Sant <sachinp at linux.vnet.ibm.com>

Thanks
-Sachin
> diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
> index ad299e72ec30..9488b63dfc87 100644
> --- a/arch/powerpc/mm/mem.c
> +++ b/arch/powerpc/mm/mem.c
> @@ -121,7 +121,7 @@ static void flush_dcache_range_chunked(unsigned long start, unsigned long stop,
> 	unsigned long i;
> 
> 	for (i = start; i < stop; i += chunk) {
> -		flush_dcache_range(i, min(stop, start + chunk));
> +		flush_dcache_range(i, min(stop, i + chunk));
> 		cond_resched();
> 	}
> }
> -- 
> 2.23.0
> 



More information about the Linuxppc-dev mailing list