On 2018/12/2 20:30, Konrad Rzeszutek Wilk wrote: > On Tue, Oct 30, 2018 at 07:06:10PM +0800, He Zhe wrote: >> >> On 2018/10/23 19:14, He Zhe wrote: >>> On 2018/10/23 03:29, Konrad Rzeszutek Wilk wrote: >>>> On Sat, Sep 22, 2018 at 08:56:58PM +0800, He Zhe wrote: >>>>> May I have your input? >>>> Alternatively would it make more sense for it to assume some default >>>> value? >>> Maybe, but the original code has no default value and I have no idea >>> what default value is proper here. >> Can anyone give some suggestions? Though I'd prefer to do nothing when >> no option is provided. > One provided the paramter for a reason. I would just do a small one, say > 4MB.
OK. Thanks, I'll send v2. Zhe >> Thanks, >> Zhe >> >>> Zhe >>> >>>>> Thanks, >>>>> Zhe >>>>> >>>>> On 2018年09月17日 11:27, [email protected] wrote: >>>>>> From: He Zhe <[email protected]> >>>>>> >>>>>> setup_io_tlb_npages does not check input argument before passing it >>>>>> to isdigit. The argument would be a NULL pointer if "swiotlb", without >>>>>> its value, is set in command line and thus causes the following panic. >>>>>> >>>>>> PANIC: early exception 0xe3 IP 10:ffffffffbb9b8e9f error 0 cr2 0x0 >>>>>> [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted >>>>>> 4.19.0-rc3-yocto-standard+ #9 >>>>>> [ 0.000000] RIP: 0010:setup_io_tlb_npages+0xf/0x95 >>>>>> ... >>>>>> [ 0.000000] Call Trace: >>>>>> [ 0.000000] do_early_param+0x57/0x8e >>>>>> [ 0.000000] parse_args+0x208/0x320 >>>>>> [ 0.000000] ? rdinit_setup+0x30/0x30 >>>>>> [ 0.000000] parse_early_options+0x29/0x2d >>>>>> [ 0.000000] ? rdinit_setup+0x30/0x30 >>>>>> [ 0.000000] parse_early_param+0x36/0x4d >>>>>> [ 0.000000] setup_arch+0x336/0x99e >>>>>> [ 0.000000] start_kernel+0x6f/0x4e6 >>>>>> [ 0.000000] x86_64_start_reservations+0x24/0x26 >>>>>> [ 0.000000] x86_64_start_kernel+0x6f/0x72 >>>>>> [ 0.000000] secondary_startup_64+0xa4/0xb0 >>>>>> >>>>>> This patch adds a check to prevent the panic. >>>>>> >>>>>> Signed-off-by: He Zhe <[email protected]> >>>>>> Cc: [email protected] >>>>>> Cc: [email protected] >>>>>> Cc: [email protected] >>>>>> Cc: [email protected] >>>>>> Cc: [email protected] >>>>>> --- >>>>>> kernel/dma/swiotlb.c | 5 +++++ >>>>>> 1 file changed, 5 insertions(+) >>>>>> >>>>>> diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c >>>>>> index 4f8a6db..46fc34e 100644 >>>>>> --- a/kernel/dma/swiotlb.c >>>>>> +++ b/kernel/dma/swiotlb.c >>>>>> @@ -109,6 +109,11 @@ static int late_alloc; >>>>>> static int __init >>>>>> setup_io_tlb_npages(char *str) >>>>>> { >>>>>> + if (!str) { >>>>>> + pr_err("Config string not provided\n"); >>>>>> + return -EINVAL; >>>>>> + } >>>>>> + >>>>>> if (isdigit(*str)) { >>>>>> io_tlb_nslabs = simple_strtoul(str, &str, 0); >>>>>> /* avoid tail segment of size < IO_TLB_SEGSIZE */ >>>>> _______________________________________________ >>>>> iommu mailing list >>>>> [email protected] >>>>> https://lists.linuxfoundation.org/mailman/listinfo/iommu _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
