From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59828) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dMvQl-0006Gr-3Y for qemu-devel@nongnu.org; Mon, 19 Jun 2017 08:05:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dMvQj-0005CN-Hl for qemu-devel@nongnu.org; Mon, 19 Jun 2017 08:05:19 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44064) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dMvQj-0005Bt-8b for qemu-devel@nongnu.org; Mon, 19 Jun 2017 08:05:17 -0400 From: David Hildenbrand References: <20170615203735.19649-1-rth@twiddle.net> <7998cb6b-018e-8069-9d11-a3e1e4e70380@redhat.com> Message-ID: <429793f7-a3c1-91ec-9a83-908ee779e703@redhat.com> Date: Mon, 19 Jun 2017 14:05:13 +0200 MIME-Version: 1.0 In-Reply-To: <7998cb6b-018e-8069-9d11-a3e1e4e70380@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] target/s390x: Implement CSST List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Richard Henderson , qemu-devel@nongnu.org Cc: thuth@redhat.com, aurelien@aurel32.net On 19.06.2017 12:03, David Hildenbrand wrote: > On 15.06.2017 22:37, Richard Henderson wrote: >> There are no uses in a Linux system with which to test, >> but it Looks Right by my reading of the PoO. > > I am using next.git/master with this patch applied: > https://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git/commit/?h=features&id=8aa8680aa383bf6e2ac > > I am using QEMU with the mvcos patch and your patch applied (and a patch > that allows enabling csst/csst2). > > I am using the following qemu command line: > > #!/bin/bash > /home/dhildenb/git/qemu/s390x-softmmu/qemu-system-s390x \ > -nographic -nodefaults -machine s390-ccw-virtio,accel=tcg \ > -cpu qemu,mvcos=on,stfle=on,ldisp=on,ldisphp=on,\ > eimm=on,stckf=on,csst=on,csst2=on,ginste=on,exrl=on\ > -m 256M -smp 1 -chardev stdio,id=con0 \ > -device sclpconsole,chardev=con0 \ > -kernel vmlinux -initrd /home/dhildenb/initrd.debian > > Right now, I can start a z9 compiled kernel. > > When trying to start a z10 compiled kernel (which generates many csst), > qemu simply crashes / the guests exits (have to debug) without any > command line output. > > So either something in csst is broken or in the other instructions for z10. > With CONFIG_DEBUG_LOCKDEP I get a pgm exception in check_no_collision() and the kernel can't find an exception table for it, resulting in a panic(). #0 0x00000000001cf584 in check_no_collision (chain=, hlock=, curr=) at kernel/locking/lockdep.c:2111 #1 lookup_chain_cache (chain_key=, hlock=, curr=) at kernel/locking/lockdep.c:2158 #2 validate_chain (curr=0xdad300 , hlock=0x18398c8 , chain_head=, chain_key=10957502631322533163, lock=) at kernel/locking/lockdep.c:2252 #3 0x00000000001d089a in __lock_acquire (lock=, subclass=, trylock=0, read=0, check=1, hardirqs_off=, nest_lock=0x0, ip=15545474, references=, pin_count=) at kernel/locking/lockdep.c:3367 #4 0x00000000001d15a6 in lock_acquire (lock=, subclass=, trylock=, read=, check=1, nest_lock=0x0, ip=15545474) at kernel/locking/lockdep.c:3855 #5 0x00000000009b76cc in __mutex_lock_common (use_ww_ctx=, ww_ctx=, ip=, nest_lock=, subclass=, state=, lock=) at kernel/locking/mutex.c:756 #6 __mutex_lock (lock=0xded840 , state=2, subclass=0, nest_lock=0x0, ip=) at kernel/locking/mutex.c:893 #7 0x00000000009b801a in mutex_lock_nested (lock=, subclass=) at kernel/locking/mutex.c:908 #8 0x0000000000ed3482 in cgroup_init_subsys (ss=0xdd2340 , early=true) at kernel/cgroup/cgroup.c:4403 #9 0x0000000000ed3752 in cgroup_init_early () at kernel/cgroup/cgroup.c:4481 #10 0x0000000000ebd79a in start_kernel () at init/main.c:502 #11 0x0000000000100020 in _stext () at arch/s390/kernel/head64.S:100 1cf552: e3 10 c0 30 00 04 lg %r1,48(%r12) 1cf558: eb 11 00 33 00 0c srlg %r1,%r1,51 1cf55e: eb c1 00 05 00 0d sllg %r12,%r1,5 1cf564: b9 09 00 c1 sgr %r12,%r1 1cf568: eb cc 00 04 00 0d sllg %r12,%r12,4 1cf56e: e3 c0 d0 28 00 08 ag %r12,40(%r13) 1cf574: a7 f4 ff 6f j 1cf452 if (DEBUG_LOCKS_WARN_ON(chain->depth != curr->lockdep_depth - (i - 1))) { 1cf578: c0 30 00 4c cc e3 larl %r3,b68f3e 1cf57e: c0 20 00 4c 95 37 larl %r2,b61fec 1cf584: c0 e5 00 07 f1 2e brasl %r14,2cd7e0 1cf58a: a7 f4 00 01 j 1cf58c 1cf58e: a7 f4 fc d9 j 1cef40 Without CONFIG_DEBUG_LOCKDEP: I get a similar crash in static void __init mm_init(void). Not sure yet what the real root cause is. Maybe something not related to CSST. -- Thanks, David