Date: Thu, 31 Aug 2017 10:25:08 +0000 From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 221957] cam iosched: Add a handler for the quanta sysctl to enforce valid values Message-ID: <bug-221957-8@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D221957 Bug ID: 221957 Summary: cam iosched: Add a handler for the quanta sysctl to enforce valid values Product: Base System Version: CURRENT Hardware: Any OS: Any Status: New Keywords: patch Severity: Affects Some People Priority: --- Component: kern Assignee: freebsd-bugs@FreeBSD.org Reporter: fk@fabiankeil.de Flags: mfc-stable11? Created attachment 185948 --> https://bugs.freebsd.org/bugzilla/attachment.cgi?id=3D185948&action= =3Dedit cam iosched: Add a handler for the quanta sysctl to enforce valid values The attached patch adds a handler for the iosched quanta sysctl to enforce valid values Invalid values can result in devision-by-zero panics and other undesirable behaviour. Example panic: Fatal trap 18: integer divide fault while in kernel mode cpuid =3D 0; apic id =3D 00 instruction pointer =3D 0x20:0xffffffff802998e5 stack pointer =3D 0x28:0xfffffe01ea3bf8d0 frame pointer =3D 0x28:0xfffffe01ea3bf900 code segment =3D base 0x0, limit 0xfffff, type 0x1b =3D DPL 0, pres 1, long 1, def32 0, gran 1 processor eflags =3D interrupt enabled, resume, IOPL =3D 0 current process =3D 12 (swi4: clock (0)) trap number =3D 18 panic: integer divide fault cpuid =3D 0 KDB: stack backtrace: db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe01ea3bf510 vpanic() at vpanic+0x186/frame 0xfffffe01ea3bf590 panic() at panic+0x43/frame 0xfffffe01ea3bf5f0 trap_fatal() at trap_fatal+0x322/frame 0xfffffe01ea3bf640 trap() at trap+0x5e/frame 0xfffffe01ea3bf800 calltrap() at calltrap+0x8/frame 0xfffffe01ea3bf800 --- trap 0x12, rip =3D 0xffffffff802998e5, rsp =3D 0xfffffe01ea3bf8d0, r= bp =3D 0xfffffe01ea3bf900 --- cam_iosched_ticker() at cam_iosched_ticker+0x25/frame 0xfffffe01ea3bf900 softclock_call_cc() at softclock_call_cc+0x13e/frame 0xfffffe01ea3bf9b0 softclock() at softclock+0xb9/frame 0xfffffe01ea3bf9e0 intr_event_execute_handlers() at intr_event_execute_handlers+0xec/frame 0xfffffe01ea3bfa20 ithread_loop() at ithread_loop+0xd6/frame 0xfffffe01ea3bfa70 fork_exit() at fork_exit+0x85/frame 0xfffffe01ea3bfab0 fork_trampoline() at fork_trampoline+0xe/frame 0xfffffe01ea3bfab0 --- trap 0, rip =3D 0, rsp =3D 0, rbp =3D 0 --- Uptime: 2h29m20s Dumping 1165 out of 8055 MB:..2%..11%..21%..31%..42%..51%..61%..71%..81%..91% Obtained from: ElectroBSD --=20 You are receiving this mail because: You are the assignee for the bug.=
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