Mark Millard
2018-Oct-20 09:09 UTC
head -r338804 boots threadripper 1950X fine; head -r338810+ do not; -r338807 seems implicated
On 2018-Oct-20, at 1:39 AM, Mark Millard <marklmi at yahoo.com> wrote:> I attempted to jump from head -r334014 to -r339076 > on a threadripper 1950X board and the boot fails. > This is both native booting and under Hyper-V, > same machine and root file system in both cases.I did my investigation under Hyper-V after seeing a boot failure native. Looks like the native failure is even earlier, before db> is even possible, possibly during early loader activity. So this report is really for running under Hyper-V: -r338804 boots and -r338810 does not. By contrast -r334804 does not boot native. (But I've little information for that context.) Sorry for the confusion. I rushed the report in hopes of getting to sleep. It was not to be.> It fails just after the FreeBSD/SMP lines, > reporting "kernel trap 9 with interrupts disabled". > > It fails in pmap_force_invaldiate_cache_range at > a clflusl (%rax) instruction that produces a > "Fatal trap 9: general protection fault while > in kernel mode". cpudid=0 apic id= 00 > > I used kernel.txz files from: > > https://artifact.ci.freebsd.org/snapshot/head/r*/amd64/amd64/ > > to narrow the range of kernel builds for working -> failing > and got: > > -r338804 boots fine > (no amd64 kernel builds between to try) > -r338810+ fails (any that I tried, anyway) > > In that range is -r338807 : > > QUOTE > Author: kib > Date: Wed Sep 19 19:35:02 2018 > New Revision: 338807 > URL: > https://svnweb.freebsd.org/changeset/base/338807 > > > Log: > Convert x86 cache invalidation functions to ifuncs. > > This simplifies the runtime logic and reduces the number of > runtime-constant branches. > > Reviewed by: alc, markj > Sponsored by: The FreeBSD Foundation > Approved by: re (gjb) > Differential revision: > https://reviews.freebsd.org/D16736 > > Modified: > head/sys/amd64/amd64/pmap.c > head/sys/amd64/include/pmap.h > head/sys/dev/drm2/drm_os_freebsd.c > head/sys/dev/drm2/i915/intel_ringbuffer.c > head/sys/i386/i386/pmap.c > head/sys/i386/i386/vm_machdep.c > head/sys/i386/include/pmap.h > head/sys/x86/iommu/intel_utils.c > END QUOTE > > There do seem to be changes associated with > clflush(...) use. Looking at: > > https://svnweb.freebsd.org/base/head/sys/amd64/amd64/pmap.c?annotate=339432 > > it appears that pmap_force_invalidate_cache_range has not > changed since -r338807. > > It seems that -r338806 and -r3388810 would be unlikely > contributors.==Mark Millard marklmi at yahoo.com ( dsl-only.net went away in early 2018-Mar)
Mark Millard
2018-Oct-22 02:55 UTC
head -r338804 boots threadripper 1950X fine; head -r338810+ do not; -r338807 seems implicated
[I built based on WITHOUT_ZFS= for other reasons. But, after installing the build, Hyper-V based boots are working.] On 2018-Oct-20, at 2:09 AM, Mark Millard <marklmi at yahoo.com> wrote:> On 2018-Oct-20, at 1:39 AM, Mark Millard <marklmi at yahoo.com> wrote: > >> I attempted to jump from head -r334014 to -r339076 >> on a threadripper 1950X board and the boot fails. >> This is both native booting and under Hyper-V, >> same machine and root file system in both cases. > > I did my investigation under Hyper-V after seeing > a boot failure native. > > Looks like the native failure is even earlier, > before db> is even possible, possibly during > early loader activity. > > So this report is really for running under > Hyper-V: -r338804 boots and -r338810 does > not. By contrast -r334804 does not boot native. > (But I've little information for that context.) > > Sorry for the confusion. I rushed the report > in hopes of getting to sleep. It was not to be. > >> It fails just after the FreeBSD/SMP lines, >> reporting "kernel trap 9 with interrupts disabled". >> >> It fails in pmap_force_invaldiate_cache_range at >> a clflusl (%rax) instruction that produces a >> "Fatal trap 9: general protection fault while >> in kernel mode". cpudid=0 apic id= 00 >> >> I used kernel.txz files from: >> >> https://artifact.ci.freebsd.org/snapshot/head/r*/amd64/amd64/ >> >> to narrow the range of kernel builds for working -> failing >> and got: >> >> -r338804 boots fine >> (no amd64 kernel builds between to try) >> -r338810+ fails (any that I tried, anyway) >> >> In that range is -r338807 : >> >> QUOTE >> Author: kib >> Date: Wed Sep 19 19:35:02 2018 >> New Revision: 338807 >> URL: >> https://svnweb.freebsd.org/changeset/base/338807 >> >> >> Log: >> Convert x86 cache invalidation functions to ifuncs. >> >> This simplifies the runtime logic and reduces the number of >> runtime-constant branches. >> >> Reviewed by: alc, markj >> Sponsored by: The FreeBSD Foundation >> Approved by: re (gjb) >> Differential revision: >> https://reviews.freebsd.org/D16736 >> >> Modified: >> head/sys/amd64/amd64/pmap.c >> head/sys/amd64/include/pmap.h >> head/sys/dev/drm2/drm_os_freebsd.c >> head/sys/dev/drm2/i915/intel_ringbuffer.c >> head/sys/i386/i386/pmap.c >> head/sys/i386/i386/vm_machdep.c >> head/sys/i386/include/pmap.h >> head/sys/x86/iommu/intel_utils.c >> END QUOTE >> >> There do seem to be changes associated with >> clflush(...) use. Looking at: >> >> https://svnweb.freebsd.org/base/head/sys/amd64/amd64/pmap.c?annotate=339432 >> >> it appears that pmap_force_invalidate_cache_range has not >> changed since -r338807. >> >> It seems that -r338806 and -r3388810 would be unlikely >> contributors. >I went after my native-boot loader problem first because I could switch kernels via the loader for booting FreeBSD under Hyper-V. Switching loaders is more of a problem. In order to avoid the loader-time crash I switched to building installing based on WITHOUT_ZFS= . I've had no active use of ZFS in years. (The old official-build loaders that worked were non-ZFS ones.) This took care of the native-boot loader-crash --and, to my surprise, also the Hyper-V-boot kernel-time crash. My private builds now boot the 1950X in both contexts just fine. During my early investigation I did pick up specific changes from after -r339076 that seemed to be tied to Ryzen and such. (They made no difference to the boot problems at the time but I saw no reason to remove them.) # uname -apKU FreeBSD FBSDFSSD 12.0-ALPHA8 FreeBSD 12.0-ALPHA8 #5 r339076:339432M: Sun Oct 21 16:44:25 PDT 2018 markmi at FBSDFSSD:/usr/obj/amd64_clang/amd64.amd64/usr/src/amd64.amd64/sys/GENERIC-NODBG amd64 amd64 1200084 1200084 ==Mark Millard marklmi at yahoo.com ( dsl-only.net went away in early 2018-Mar)