On Mon, 17 Jul 2017, Johnny Hughes wrote: > Are the testing kernels (kernel-4.9.37-29.el7 and kernel-4.9.37-29.el6, > with the one config file change) working for everyone: > > (turn off: CONFIG_IO_STRICT_DEVMEM) Hello. Maybe it's not the most appropriate thread or time, but I have been signalling it before: 4.9.* kernels do not work well for me any more (and for other people neither, as I know). Last stable kernel was 4.9.13-22. Since 4.9.25-26 I do often get: on 3 supermicro servers (different generations): - memory allocation errors on Dom0 and corresponding lost lost page writes due to buffer I/O error on PV guests - after such memory allocation error od dom0 I have spotted also: - NFS client hangups on guests (server not responding, still trying => server OK) - iptables lockups on PV guest reboot on 1 supermicro server: - memory allocation errors on Dom0 and SATA lockups (many, if not SATA channels at - once): exception Emask 0x0 SAct 0x20 SErr 0x0 action 0x6 frozen hard resetting link failed to IDENTIFY (I/O error, err_mask=0x4) then: blk_update_request: I/O error, dev sd., sector .... All of these machines have been tested with memtest, no detected memory problems. No such things occur, when I boot 4.9.13-22 Most of my guests are centos 6 x86_64, bridged. Do anyone had such problems, dealt with it somehow? Since spotting these errors I have done many tests, compiled and tested to point out single code change (kernel version, patch) - no conclusions yet. But one has changed much between 4.9.13 and 4.9.25: kernel size and configuration. 4.9.13 size was 6MB and 4.9.24 is 7.1MB. Many modules have been compiled into kernel, here is shortened, but significant list: - iptables (NETFILTER_XTABLES, IP_NF_FILTER, IP_NF_TARGET_REJECT) - SATA_AHCI - ATA_AHCI (PATA, what a heck?) - FBDEV_FRONTEND - HID_MAGICKMOUSE - HID_NTRIG - USB_XHCI - INTEL_SMARTCONNECT Do we really need these compiled into dom0 kernel? I assume, that the biggest change in size is due to yama and CRYPTO_*, and it is not going to change. Regards, -- Piotr Gackiewicz Intertele S.A. - operator systemów ITL.PL i DOMENY.ITL.PL al. T. Rejtana 10, 35-310 Rzeszów TEL: +48 17 8507580, FAX: +48 17 8520275 http://www.itl.pl - niezawodne usługi hostingowe http://domeny.itl.pl - tanie domeny internetowe http://www.intertele.pl