Date: Wed, 28 Jan 2015 11:54:44 -0800 From: Neel Natu <neelnatu@gmail.com> To: Gleb Smirnoff <glebius@freebsd.org> Cc: Konstantin Belousov <kostikbel@gmail.com>, "current@freebsd.org" <current@freebsd.org>, Peter Grehan <grehan@freebsd.org> Subject: Re: panic in softdep_slowdown() Message-ID: <CAFgRE9EK4TE6_Qp9KsHjJJi4qeWisaAdeaMV8PtGeUXpTP1VJw@mail.gmail.com> In-Reply-To: <20150128193315.GC15484@glebius.int.ru> References: <20150127203103.GZ15484@glebius.int.ru> <20150128104842.GL42409@kib.kiev.ua> <20150128182230.GB15484@glebius.int.ru> <20150128190441.GO42409@kib.kiev.ua> <20150128193315.GC15484@glebius.int.ru>
next in thread | previous in thread | raw e-mail | index | archive | help
Hi Gleb, On Wed, Jan 28, 2015 at 11:33 AM, Gleb Smirnoff <glebius@freebsd.org> wrote: > On Wed, Jan 28, 2015 at 09:04:42PM +0200, Konstantin Belousov wrote: > K> > I can't see where integer divide fault can happen with stat_flush_threads=1 :( > K> > K> Look at the exact asm instruction which faulted, also look at the registers > K> content. > K> > K> It might be hypervisor bug, after all. > > Yes, for me it looks like it. %edx should be one as well as -0x44(%rbp). > > 0xffffffff80895d43 <softdep_slowdown+435>: mov -0x20(%rbp),%ecx > 0xffffffff80895d46 <softdep_slowdown+438>: mov %ecx,%edx > 0xffffffff80895d48 <softdep_slowdown+440>: shr $0x1f,%edx > 0xffffffff80895d4b <softdep_slowdown+443>: add %edx,%ecx > 0xffffffff80895d4d <softdep_slowdown+445>: sar %ecx > 0xffffffff80895d4f <softdep_slowdown+447>: mov 0xffffffff80ee24c8,%edx > 0xffffffff80895d56 <softdep_slowdown+454>: mov %rax,-0x40(%rbp) > 0xffffffff80895d5a <softdep_slowdown+458>: mov %ecx,%eax > 0xffffffff80895d5c <softdep_slowdown+460>: mov %edx,-0x44(%rbp) > 0xffffffff80895d5f <softdep_slowdown+463>: cltd > 0xffffffff80895d60 <softdep_slowdown+464>: mov -0x44(%rbp),%ecx > 0xffffffff80895d63 <softdep_slowdown+467>: idiv %ecx > > (kgdb) p &stat_flush_threads > $5 = (int *) 0xffffffff80ee24c8 > (kgdb) info registers > rax 0x12b86 76678 > rbx 0x4 4 > rcx 0x0 0 > rdx 0x0 0 > rsi 0x3e8 1000 > rdi 0x99 153 > rbp 0xfffffe001eb5f2b0 0xfffffe001eb5f2b0 > ... > (kgdb) p *(int *)($rbp - 0x44) > $4 = 0 > (kgdb) p *(int *)($rbp - 0x40) > $8 = 0 > (kgdb) p &max_softdeps_hard > $11 = (int *) 0xfffffe001eb5f290 > (kgdb) p (int *)($rbp - 0x20) > $12 = (int *) 0xfffffe001eb5f290 > (kgdb) p max_softdeps_hard > $10 = 153357 > Can you upload the core file and the kernel someplace that I can access? best Neel > -- > Totus tuus, Glebius. > _______________________________________________ > freebsd-current@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscribe@freebsd.org"
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAFgRE9EK4TE6_Qp9KsHjJJi4qeWisaAdeaMV8PtGeUXpTP1VJw>