Re: [Xen-devel] Linux 4.8-rc8 with Xen for-linus-4.9 branch: dom0 crashes on boot

[Sander Eikelenboom <linux@xxxxxxxxxxxxxx>]

On 2016-10-02 14:38, Boris Ostrovsky wrote:
> On 10/02/2016 08:26 AM, Sander Eikelenboom wrote:
> > On 2016-10-02 14:08, Andrew Cooper wrote:
> > > On 02/10/2016 12:46, Sander Eikelenboom wrote:
> > > > Hi All,
> > > >
> > > > Since the new merge window is emerging I took the liberty of testing 
> > > > a
> > > > linux 4.8-rc8 tree with
> > > > the Xen for-linus-4.9 branch pulled on top.
> > > > Unfortunately this crashes dom0 early in boot under Xen.
> > > > On bare-metal the same kernel boots fine.
> > > > Under Xen a linux 4.8-rc8 kernel without the Xen branch pulled on 
> > > > top,
> > > > also boots fine.
> > > So this looks to be a regression in the Xen for-linux-4.9 branch.
> > >
> > > > Hypervisor is a recentish xen-unstable build.
> > > >
> > > > The serial log is below.
> > > > <snip>
> > > > (XEN) [2016-10-02 11:31:53.106] Scrubbing Free RAM on 1 nodes using 
> > > > 6
> > > > CPUs
> > > > (XEN) [2016-10-02 11:31:53.217] .............................done.
> > > > (XEN) [2016-10-02 11:31:56.242] Initial low memory virq threshold 
> > > > set
> > > > at 0x4000 pages.
> > > > (XEN) [2016-10-02 11:31:56.260] Std. Loglevel: All
> > > > (XEN) [2016-10-02 11:31:56.277] Guest Loglevel: All
> > > > (XEN) [2016-10-02 11:31:56.295] Xen is relinquishing VGA console.
> > > > (XEN) [2016-10-02 11:31:56.396] *** Serial input -> DOM0 (type
> > > > 'CTRL-a' three times to switch input to Xen)
> > > > (XEN) [2016-10-02 11:31:56.396] Freed 308kB init memory
> > > > (XEN) [2016-10-02 11:31:56.397] d0v0: unhandled page fault (ec=0000)
> > > > (XEN) [2016-10-02 11:31:56.397] Pagetable walk from 
> > > > 0000000000000001:
> > > > (XEN) [2016-10-02 11:31:56.397]  L4[0x000] = 0000000000000000
> > > > ffffffffffffffff
> > > > (XEN) [2016-10-02 11:31:56.397] domain_crash_sync called from 
> > > > entry.S:
> > > > fault at ffff82d080244960 entry.o#create_bounce_frame+0x145/0x154
> > > > (XEN) [2016-10-02 11:31:56.397] Domain 0 (vcpu#0) crashed on cpu#0:
> > > > (XEN) [2016-10-02 11:31:56.397] ----[ Xen-4.8-unstable  x86_64
> > > > debug=y   Not tainted ]----
> > > > (XEN) [2016-10-02 11:31:56.397] CPU:    0
> > > > (XEN) [2016-10-02 11:31:56.397] RIP:    e033:[<ffffffff8101fdb9>]
> > > > (XEN) [2016-10-02 11:31:56.397] RFLAGS: 0000000000000286   EM: 1
> > > > CONTEXT: pv guest (d0v0)
> > > > (XEN) [2016-10-02 11:31:56.397] rax: 0000000000000000   rbx:
> > > > ffffffff82248bb0   rcx: ffffffff8101bc10
> > > > (XEN) [2016-10-02 11:31:56.397] rdx: 0000000000000001   rsi:
> > > > ffffffff81f0aa50   rdi: ffffffff82248bb0
> > > > (XEN) [2016-10-02 11:31:56.397] rbp: ffffffff82203e50   rsp:
> > > > ffffffff82203dc0   r8:  ffffffff8101b550
> > > > (XEN) [2016-10-02 11:31:56.397] r9:  0000000000000000   r10:
> > > > 0000000000000000   r11: 0000000080802001
> > > > (XEN) [2016-10-02 11:31:56.397] r12: 0000000000000000   r13:
> > > > 0000000000000000   r14: ffffffff82215580
> > > > (XEN) [2016-10-02 11:31:56.397] r15: 0000000000000000   cr0:
> > > > 000000008005003b   cr4: 00000000000006e0
> > > > (XEN) [2016-10-02 11:31:56.397] cr3: 000000054a601000   cr2:
> > > > 0000000000000001
> > > > (XEN) [2016-10-02 11:31:56.397] ds: 0000   es: 0000   fs: 0000   gs:
> > > > 0000   ss: e02b   cs: e033
> > > > (XEN) [2016-10-02 11:31:56.397] Guest stack trace from
> > > > rsp=ffffffff82203dc0:
> > > > (XEN) [2016-10-02 11:31:56.397]    ffffffff8101bc10 0000000080802001
> > > > 0000000000000000 ffffffff8101fdb9
> > > > (XEN) [2016-10-02 11:31:56.397]    000000010000e030 0000000000010086
> > > > ffffffff82203e00 000000000000e02b
> > > > (XEN) [2016-10-02 11:31:56.397]    ffffffff82203e50 ffffffff8101fcb5
> > > > 0000000080802001 0000000000000000
> > > > (XEN) [2016-10-02 11:31:56.397]    0000000000000000 ffffffff8101b550
> > > > ffffffff82248bb0 ffffffff81f0aa50
> > > > (XEN) [2016-10-02 11:31:56.397]    0000000000000001 ffffffff8101bc10
> > > > ffffffff82203eb8 ffffffff81b7e9f4
> > > > (XEN) [2016-10-02 11:31:56.397]    0000000000000000 ffffffff82203ea8
> > > > 0000000080802001 0000000000000004
> > > > (XEN) [2016-10-02 11:31:56.397]    ffffffff8101baa2 ffffffff82203f40
> > > > ffffffff82248bb0 0000000000000000
> > > > (XEN) [2016-10-02 11:31:56.397]    0000000000000000 ffffffff8101bc10
> > > > 0000000000000000 ffffffff82203ed0
> > > > (XEN) [2016-10-02 11:31:56.397]    ffffffff81b7ed45 0000000000000013
> > > > ffffffff82203ee0 ffffffff810cc127
> > > > (XEN) [2016-10-02 11:31:56.397]    ffffffff82203f28 ffffffff810ccdab
> > > > ffffffff81f0aa50 ffffffff8101b550
> > > > (XEN) [2016-10-02 11:31:56.397]    ffffffff82203f60 ffffffff82203f5c
> > > > 0000000000000000 0000000000000000
> > > > (XEN) [2016-10-02 11:31:56.397]    0000000000000000 ffffffff82203f40
> > > > ffffffff810c83be ffffffff82600000
> > > > (XEN) [2016-10-02 11:31:56.397]    ffffffff82203ff8 ffffffff8232946a
> > > > 00100fa000000000 8080200100060800
> > > > (XEN) [2016-10-02 11:31:56.397]    000000001789c3f5 0000000000000000
> > > > 0000000000000000 0000000000000000
> > > > (XEN) [2016-10-02 11:31:56.397]    0000000000000000 0000000000000000
> > > > 0000000000000000 0000000000000000
> > > > (XEN) [2016-10-02 11:31:56.397]    0000000000000000 0000000000000000
> > > > 0000000000000000 0000000000000000
> > > > (XEN) [2016-10-02 11:31:56.397]    0000000000000000 0000000000000000
> > > > 0000000000000000 0000000000000000
> > > > (XEN) [2016-10-02 11:31:56.397]    0000000000000000 0000000000000000
> > > > 0000000000000000 0000000000000000
> > > > (XEN) [2016-10-02 11:31:56.397]    0f00000060c0c748 ccccccccccccc305
> > > > cccccccccccccccc cccccccccccccccc
> > > > (XEN) [2016-10-02 11:31:56.397]    cccccccccccccccc cccccccccccccccc
> > > > cccccccccccccccc cccccccccccccccc
> > > > (XEN) [2016-10-02 11:31:56.397] Hardware Dom0 crashed: rebooting
> > > > machine in 5 seconds.
> > > Something in Linux at ffffffff8101fdb9 followed a NULL pointer.  Can 
> > > you
> > > see what it was with the linux debug symbols?
> > >
> > > ~Andrew
> > Sure thing:
> > addr2line -e vmlinux-4.8.0-rc8-20161002-linus-xennext+ 
> > ffffffff8101fdb9
> > /usr/src/new/linux-linus/arch/x86/xen/irq.c:34
> >
> > asmlinkage __visible unsigned long xen_save_fl(void)
> > {
> >         struct vcpu_info *vcpu;
> >         unsigned long flags;
> >
> >         vcpu = this_cpu_read(xen_vcpu);
> >
> >         /* flag has opposite sense of mask */
> >         flags = !vcpu->evtchn_upcall_mask;   <== WHICH IS HERE
> >
> >         /* convert to IF type flag
> >            -0 -> 0x00000000
> >            -1 -> 0xffffffff
> >         */
> >         return (-flags) & X86_EFLAGS_IF;
> > }
>
> Can you post your .config file?
>
> Our tests seem to have run fine yesterday with those branches, until
> apparently electrical problem shut down the whole test farm this 
> morning.
> -boris
Sure, it's attached.

--
Sander

Attachment: dot-config
Description: Text document

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel