On Fri, Aug 16, 2019 at 08:20:42AM -0600, Jens Axboe wrote: > On 8/16/19 1:48 AM, Ming Lei wrote: > > It is reported that sysfs buffer overflow can be triggered in case > > of too many CPU cores(>841 on 4K PAGE_SIZE) when showing CPUs in > > blk_mq_hw_sysfs_cpus_show(). > > > > This info isn't useful, given users may retrieve the CPU list > > from sw queue entries under same kobject dir, so far not see > > any active users. > > > > So remove the entry as suggested by Greg. > > I think that's a bit frivolous, there could very well be scripts or > apps that use it. Let's just fix the overflow. I am fine with either way. There are two fixes: 1) without format change: https://lore.kernel.org/linux-block/c5b1b6f3-d461-9379-7e5c-6c6bee6a7bd5@xxxxxxxxx/T/#t 2) format change: https://lore.kernel.org/linux-block/20190816070948.GD1368@xxxxxxxxx/T/#t If either one isn't fine, please let me know, and I will cook new one for you. Thanks, Ming