On 26/03/2014 22:01, Daniel Kiper wrote: > On Wed, Mar 26, 2014 at 01:57:23PM +0000, Matt Fleming wrote: >> On Wed, 26 Mar, at 02:48:45PM, Daniel Kiper wrote: >>> On my machine this function crashes on Xen so that is why I have changed >>> condition. However, if you say that this issue could be solved in >>> another way I will investigate it further. >> Daniel, could you paste the crash? Do you get a stack trace? > Here it is: > > [...] > > mapping kernel into physical memory > about to get started... > (XEN) traps.c:458:d0v0 Unhandled divide error fault/trap [#0] on VCPU 0 [ec=0000] > (XEN) domain_crash_sync called from entry.S: fault at ffff82d080229d30 int80_direct_trap+0x200/0x210 > (XEN) Domain 0 (vcpu#0) crashed on cpu#0: > (XEN) ----[ Xen-4.5-unstable x86_64 debug=y Tainted: C ]---- > (XEN) CPU: 0 > (XEN) RIP: e033:[<ffffffff816987c5>] > (XEN) RFLAGS: 0000000000000246 EM: 1 CONTEXT: pv guest > (XEN) rax: 0000000000000000 rbx: 0000000001000000 rcx: 0000000000000000 > (XEN) rdx: 0000000000000000 rsi: ffffffff814d7e7e rdi: 0000000000000000 > (XEN) rbp: ffffffff81601e88 rsp: ffffffff81601e48 r8: 0000000000000000 > (XEN) r9: 0000000000007ff0 r10: 00000000deadbeef r11: ffffffff81601df8 > (XEN) r12: ffffffff816fe010 r13: ffffffff81601f00 r14: 0000000000000000 > (XEN) r15: 0000000000000000 cr0: 0000000080050033 cr4: 00000000000026f0 > (XEN) cr3: 000000007b60d000 cr2: 0000000000000000 > (XEN) ds: 0000 es: 0000 fs: 0000 gs: 0000 ss: e02b cs: e033 > (XEN) Guest stack trace from rsp=ffffffff81601e48: > (XEN) 0000000000000000 ffffffff81601df8 ffffffff816987c5 000000010000e030 > (XEN) 0000000000010046 ffffffff81601e88 000000000000e02b ffffffff81601f00 > (XEN) ffffffff81601ed8 ffffffff8168a1a4 ffffffff81601ee8 ffffffff81601ea8 > (XEN) ffff880001e16490 ffffffffffffffff ffffffff816fe010 0000000000000000 > (XEN) 0000000000000000 0000000000000000 ffffffff81601f28 ffffffff81685a3e > (XEN) 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > (XEN) ffff880001e16000 0000000000000000 0000000000000000 0000000000000000 > (XEN) ffffffff81601f38 ffffffff816854c8 ffffffff81601ff8 ffffffff81687442 > (XEN) 0000000100000000 0000080000000623 0789cbf580802001 0300000100000032 > (XEN) 0000000000000005 0000000000000000 0000000000000000 0000000000000000 > (XEN) 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > (XEN) 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > (XEN) 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > (XEN) 0000000000000000 0000000000000000 0000000000000000 0f00000060c0c748 > (XEN) ccccccccccccc305 cccccccccccccccc cccccccccccccccc cccccccccccccccc > (XEN) cccccccccccccccc cccccccccccccccc cccccccccccccccc cccccccccccccccc > (XEN) cccccccccccccccc cccccccccccccccc cccccccccccccccc cccccccccccccccc > (XEN) cccccccccccccccc cccccccccccccccc cccccccccccccccc cccccccccccccccc > (XEN) cccccccccccccccc cccccccccccccccc cccccccccccccccc cccccccccccccccc > (XEN) cccccccccccccccc cccccccccccccccc cccccccccccccccc cccccccccccccccc > (XEN) Domain 0 crashed: rebooting machine in 5 seconds. > > Some addresses are solved to: > 0xffffffff816987c5: efi_memblock_x86_reserve_range at arch/x86/platform/efi/efi.c:393 > 0xffffffff8168a1a4: setup_arch at arch/x86/kernel/setup.c:940 > 0xffffffff81685a3e: setup_command_line at init/main.c:353 > 0xffffffff816854c8: x86_64_start_reservations at arch/x86/kernel/head64.c:194 > 0xffffffff81687442: xen_start_kernel at arch/x86/xen/enlighten.c:1733 > > I am using Linus tree with latest commit b098d6726bbfb94c06d6e1097466187afddae61f > (Linux 3.14-rc8) with my patches applied excluding patch 3. > > Daniel Then all you need to do is look up ffffffff816987c5 in your linux symbols, and whichever variable is being divided on that line of source has ether has the value 0 or -1. ~Andrew -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html