On Wed, 2015-10-28 at 12:53 +0300, Stas Sergeev wrote: > 28.10.2015 03:04, Toshi Kani пишет: > > On Wed, 2015-10-28 at 07:37 +0900, Linus Torvalds wrote: > > > On Tue, Oct 27, 2015 at 11:05 PM, Stas Sergeev <s...@list.ru> wrote: > > > > > > > > I can't easily post an Oops: under X it doesn't even appear - > > > > machine freezes immediately, and under non-KMS console it is > > > > possible to get one, but difficult to screen-shot (using bare > > > > metal, not VM). Also the Oops was seemingly unrelated. > > > > And if you run "dosemu -s" under non-KMS console, you'll also > > > > reproduce this one: > > > > https://bugzilla.kernel.org/show_bug.cgi?id=97321 > > > > > > Hmm. Andrew Morton responded to that initially, but then nothing > > > happened, and now it's been another six months. Andrew? > > > > > > The arch/x86/mm/pat.c error handling does seem to be suspect. This is > > > all code several years old, so none of this is new, and I think > > > Suresh > > > is gone. Adding a few other people with recent sign-offs to that > > > file, in the hope that somebody feels like they own it.. > > > > In the case of PFNMAP, the range should always be mapped. So, I wonder > > why > > follow_phys() failed with the !pte_present() check. > > > > Stas, do you have a test program that can reproduce 97321? > Get dosemu2 from here: > https://github.com/stsp/dosemu2/releases > or from git, or get dosemu1. > Then boot your kernel with "nomodeset=1" to get a text console. > Run > > dosemu -s > > and you'll get the bug. > You don't even need to mess with FreeDOS or whatever, because > the problem happens on a very start. And since it is WARN_OCNCE, > you'll need to reboot to get it again. > You will probably need to adjust /etc/sudoers because -s means > that dosemu (a wrapper script for dosemu.bin) will try sudo so > that dosemu.bin can grab /dev/mem as root. > > If it is too complicated, let me know and I'll try to code up > a reduced test-case (but can't promise to get to that quickly). > > Thanks to everyone (esp Linus of course :-) who got involved in > finally supporting dosemu again - it was rather ill for the last > years.
I compiled "pre4" dosemu2, and ran on 4.3-rc7 kernel booted with the "nomodeset=1" option. I may be missing something, but I am not able to reproduce your problem because dosemu fails with the segfault below on my system... Program terminated with signal SIGSEGV, Segmentation fault. #0 0x0000000000421fdb in video_init () at video.c:242 242 if (Video->priv_init) (gdb) bt #0 0x0000000000421fdb in video_init () at video.c:242 #1 video_config_init () at video.c:391 #2 0x00000000004b5693 in device_init () at init.c:237 #3 0x000000000041ea3a in main (argc=3, argv=0x7fff70851d28) at emu.c:356 (gdb) p Video $1 = (struct video_system *) 0x0 Thanks, -Toshi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
