From: Joerg Roedel <[email protected]> When the crashkernel is loaded above 4GiB in memory the first kernel only allocates 72MiB of low-memory for the DMA requirements of the second kernel. On systems with many devices this is not enough and causes device driver initialization errors and failed crash dumps. Set this default value to 256MiB to make sure there is enough memory available for DMA.
Signed-off-by: Joerg Roedel <[email protected]> --- arch/x86/kernel/setup.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index ab08aa2..1227e30 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -536,8 +536,11 @@ static void __init reserve_crashkernel_low(void) * swiotlb overflow buffer: now is hardcoded to 32k. * We round it to 8M for other buffers that * may need to stay low too. + * Also make sure we allocate enough extra memory + * low memory so that we don't run out of DMA + * buffers for 32bit devices. */ - low_size = swiotlb_size_or_default() + (8UL<<20); + low_size = max(swiotlb_size_or_default() + (8UL<<20), 256UL<<20); auto_set = true; } else { /* passed with crashkernel=0,low ? */ -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
