simulating wireless device (if_alloc panic, VirtualBox, VIMAGE)
Hi, I hope I am on the write place, second try... I have written a module that loads fake wifi devices (wtap?) and distributes packets between them. For now I use route command to route packets between them from upper layers (TCP,...). I want to take it to next step and create jails with VNET. I started reading Julian Elischer's Vimage: what is it? and he says that if I am writing hardware drivers I dont need to make any changes when I enable VIMAGE option on the kernel, because each one will have their own stack. I can give a more detailed explanation on how my module works. But for now I get a panic when calling if_alloc() when using option VIMAGE. Thank you, My setup: FreeBSD Current 201010 guest on VirtualBox on Ubuntu 10.04. Kernel page fault with the following non-sleepable locks held: exclusive rw ifnet_rw (ifnet_rw) r = 0 (0xc0fc8284) locked @ /usr/src/sys/net/if.c:414 KDB: stack backtrace: db_trace_self_wrapper(c0cf3cdb,1,0,0,0,...) at db_trace_self_wrapper+0x26 kdb_backtrace(19e,1,,c0f9b194,c2fc9a1c,...) at kdb_backtrace+0x2a _witness_debugger(c0cf6408,c2fc9a30,4,1,0,...) at _witness_debugger+0x25 witness_warn(5,0,c0d2c479,3,c4070d48,...) at witness_warn+0x1fe trap(c2fc9abc) at trap+0x195 calltrap() at calltrap+0x6 --- trap 0xc, eip = 0xc0970999, esp = 0xc2fc9afc, ebp = 0xc2fc9b1c --- ifindex_alloc_locked(c0d003cf,c2fc9b36,19e,19e,c15ab714,...) at ifindex_alloc_locked+0x19 if_alloc(47,c4085a16,3,c0de9614,c32aa780,...) at if_alloc+0x85 wtap_attach(c31a7800,c40857c0,0,4,0,...) at wtap_attach+0x29 new_wtap(c32aa780,0,c2fc9bf0,c083ac9b,c3cbb200,...) at new_wtap+0x9b wtap_ioctl(c3cbb200,80045701,c31edaa0,1,c3f90b40,...) at wtap_ioctl+0x36 devfs_ioctl_f(c3cfe3b8,80045701,c31edaa0,c3185d00,c3f90b40,...) at devfs_ioctl_f+0x10b kern_ioctl(c3f90b40,3,80045701,c31edaa0,fc9cec,...) at kern_ioctl+0x20d ioctl(c3f90b40,c2fc9cec,c2fc9d28,c0cf5783,0,...) at ioctl+0x134 syscallenter(c3f90b40,c2fc9ce4,c2fc9ce4,0,0,...) at syscallenter+0x263 syscall(c2fc9d28) at syscall+0x34 Xint0x80_syscall() at Xint0x80_syscall+0x21 --- syscall (54, FreeBSD ELF32, ioctl), eip = 0x28181203, esp = 0xbfbfec3c, ebp = 0xbfbfec58 --- Fatal trap 12: page fault while in kernel mode cpuid = 0; apic id = 00 fault virtual address = 0x18 fault code = supervisor read, page not present instruction pointer = 0x20:0xc0970999 stack pointer = 0x28:0xc2fc9afc frame pointer = 0x28:0xc2fc9b1c code segment= base 0x0, limit 0xf, type 0x1b = DPL 0, pres 1, def32 1, gran 1 processor eflags= interrupt enabled, resume, IOPL = 0 current process = 1203 (ioctl) panic: from debugger cpuid = 0 Uptime: 21s Physical memory: 495 MB Dumping 55 MB: 40 24 8 -- //Monthadar Al Jaberi ___ freebsd-virtualization@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-virtualization To unsubscribe, send any mail to freebsd-virtualization-unsubscr...@freebsd.org
Re: simulating wireless device (if_alloc panic, VirtualBox, VIMAGE)
On 2/1/11 8:40 AM, Monthadar Al Jaberi wrote: Hi, I hope I am on the write place, second try... I have written a module that loads fake wifi devices (wtap?) and distributes packets between them. For now I use route command to route packets between them from upper layers (TCP,...). I want to take it to next step and create jails with VNET. I started reading Julian Elischer's Vimage: what is it? and he says that if I am writing hardware drivers I dont need to make any changes when I enable VIMAGE option on the kernel, because each one will have their own stack. I can give a more detailed explanation on how my module works. But for now I get a panic when calling if_alloc() when using option VIMAGE. Thank you, while this was true to some extent it i snot 100% true now. during allocation we now try to have separate interface indexes per vimage which means that the setup routines do need to know the current vnet. it looks like wtap_ioctl or wtap_attach should have the following: (copied from the tun driver) this should not be needed from real hardware based drivers as far as I can tell. CURVNET_SET(CRED_TO_VNET(cred)); /* find any existing device, or allocate new unit number */ i = clone_create(tunclones, tun_cdevsw, u, dev, 0); [blah] if_clone_create(name, namelen, NULL); CURVNET_RESTORE(); My setup: FreeBSD Current 201010 guest on VirtualBox on Ubuntu 10.04. Kernel page fault with the following non-sleepable locks held: exclusive rw ifnet_rw (ifnet_rw) r = 0 (0xc0fc8284) locked @ /usr/src/sys/net/if.c:414 KDB: stack backtrace: db_trace_self_wrapper(c0cf3cdb,1,0,0,0,...) at db_trace_self_wrapper+0x26 kdb_backtrace(19e,1,,c0f9b194,c2fc9a1c,...) at kdb_backtrace+0x2a _witness_debugger(c0cf6408,c2fc9a30,4,1,0,...) at _witness_debugger+0x25 witness_warn(5,0,c0d2c479,3,c4070d48,...) at witness_warn+0x1fe trap(c2fc9abc) at trap+0x195 calltrap() at calltrap+0x6 --- trap 0xc, eip = 0xc0970999, esp = 0xc2fc9afc, ebp = 0xc2fc9b1c --- ifindex_alloc_locked(c0d003cf,c2fc9b36,19e,19e,c15ab714,...) at ifindex_alloc_locked+0x19 if_alloc(47,c4085a16,3,c0de9614,c32aa780,...) at if_alloc+0x85 wtap_attach(c31a7800,c40857c0,0,4,0,...) at wtap_attach+0x29 new_wtap(c32aa780,0,c2fc9bf0,c083ac9b,c3cbb200,...) at new_wtap+0x9b wtap_ioctl(c3cbb200,80045701,c31edaa0,1,c3f90b40,...) at wtap_ioctl+0x36 devfs_ioctl_f(c3cfe3b8,80045701,c31edaa0,c3185d00,c3f90b40,...) at devfs_ioctl_f+0x10b kern_ioctl(c3f90b40,3,80045701,c31edaa0,fc9cec,...) at kern_ioctl+0x20d ioctl(c3f90b40,c2fc9cec,c2fc9d28,c0cf5783,0,...) at ioctl+0x134 syscallenter(c3f90b40,c2fc9ce4,c2fc9ce4,0,0,...) at syscallenter+0x263 syscall(c2fc9d28) at syscall+0x34 Xint0x80_syscall() at Xint0x80_syscall+0x21 --- syscall (54, FreeBSD ELF32, ioctl), eip = 0x28181203, esp = 0xbfbfec3c, ebp = 0xbfbfec58 --- Fatal trap 12: page fault while in kernel mode cpuid = 0; apic id = 00 fault virtual address = 0x18 fault code = supervisor read, page not present instruction pointer = 0x20:0xc0970999 stack pointer = 0x28:0xc2fc9afc frame pointer = 0x28:0xc2fc9b1c code segment= base 0x0, limit 0xf, type 0x1b = DPL 0, pres 1, def32 1, gran 1 processor eflags= interrupt enabled, resume, IOPL = 0 current process = 1203 (ioctl) panic: from debugger cpuid = 0 Uptime: 21s Physical memory: 495 MB Dumping 55 MB: 40 24 8 ___ freebsd-virtualization@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-virtualization To unsubscribe, send any mail to freebsd-virtualization-unsubscr...@freebsd.org
Re: simulating wireless device (if_alloc panic, VirtualBox, VIMAGE)
On Tue, Feb 1, 2011 at 6:25 PM, Julian Elischer jul...@freebsd.org wrote: On 2/1/11 8:40 AM, Monthadar Al Jaberi wrote: Hi, I hope I am on the write place, second try... I have written a module that loads fake wifi devices (wtap?) and distributes packets between them. For now I use route command to route packets between them from upper layers (TCP,...). I want to take it to next step and create jails with VNET. I started reading Julian Elischer's Vimage: what is it? and he says that if I am writing hardware drivers I dont need to make any changes when I enable VIMAGE option on the kernel, because each one will have their own stack. I can give a more detailed explanation on how my module works. But for now I get a panic when calling if_alloc() when using option VIMAGE. Thank you, while this was true to some extent it i snot 100% true now. during allocation we now try to have separate interface indexes per vimage which means that the setup routines do need to know the current vnet. so I cant call if_alloc directly? it looks like wtap_ioctl or wtap_attach should have the following: (copied from the tun driver) this should not be needed from real hardware based drivers as far as I can tell. CURVNET_SET(CRED_TO_VNET(cred)); /* find any existing device, or allocate new unit number */ i = clone_create(tunclones, tun_cdevsw, u, dev, 0); [blah] if_clone_create(name, namelen, NULL); CURVNET_RESTORE(); My wtap is based on ath driver code (if_ath.c) which should look like a real device right? if_ath.c is not using VNET, as far as I can tell Currently my module creates a couple of wtaps, which I then create a corresponding wlan. These wtaps are interconnected together, so no out world yet... so I dont have struct cdev *dev Basic idea is my module have a main queue (simulating air) and each wtap have a rx_task which sends packets up to higher layers, plus callout timer for generation beacons... I will try to use CURVET_SET(...) tomo My setup: FreeBSD Current 201010 guest on VirtualBox on Ubuntu 10.04. Kernel page fault with the following non-sleepable locks held: exclusive rw ifnet_rw (ifnet_rw) r = 0 (0xc0fc8284) locked @ /usr/src/sys/net/if.c:414 KDB: stack backtrace: db_trace_self_wrapper(c0cf3cdb,1,0,0,0,...) at db_trace_self_wrapper+0x26 kdb_backtrace(19e,1,,c0f9b194,c2fc9a1c,...) at kdb_backtrace+0x2a _witness_debugger(c0cf6408,c2fc9a30,4,1,0,...) at _witness_debugger+0x25 witness_warn(5,0,c0d2c479,3,c4070d48,...) at witness_warn+0x1fe trap(c2fc9abc) at trap+0x195 calltrap() at calltrap+0x6 --- trap 0xc, eip = 0xc0970999, esp = 0xc2fc9afc, ebp = 0xc2fc9b1c --- ifindex_alloc_locked(c0d003cf,c2fc9b36,19e,19e,c15ab714,...) at ifindex_alloc_locked+0x19 if_alloc(47,c4085a16,3,c0de9614,c32aa780,...) at if_alloc+0x85 wtap_attach(c31a7800,c40857c0,0,4,0,...) at wtap_attach+0x29 new_wtap(c32aa780,0,c2fc9bf0,c083ac9b,c3cbb200,...) at new_wtap+0x9b wtap_ioctl(c3cbb200,80045701,c31edaa0,1,c3f90b40,...) at wtap_ioctl+0x36 devfs_ioctl_f(c3cfe3b8,80045701,c31edaa0,c3185d00,c3f90b40,...) at devfs_ioctl_f+0x10b kern_ioctl(c3f90b40,3,80045701,c31edaa0,fc9cec,...) at kern_ioctl+0x20d ioctl(c3f90b40,c2fc9cec,c2fc9d28,c0cf5783,0,...) at ioctl+0x134 syscallenter(c3f90b40,c2fc9ce4,c2fc9ce4,0,0,...) at syscallenter+0x263 syscall(c2fc9d28) at syscall+0x34 Xint0x80_syscall() at Xint0x80_syscall+0x21 --- syscall (54, FreeBSD ELF32, ioctl), eip = 0x28181203, esp = 0xbfbfec3c, ebp = 0xbfbfec58 --- Fatal trap 12: page fault while in kernel mode cpuid = 0; apic id = 00 fault virtual address = 0x18 fault code = supervisor read, page not present instruction pointer = 0x20:0xc0970999 stack pointer = 0x28:0xc2fc9afc frame pointer = 0x28:0xc2fc9b1c code segment = base 0x0, limit 0xf, type 0x1b = DPL 0, pres 1, def32 1, gran 1 processor eflags = interrupt enabled, resume, IOPL = 0 current process = 1203 (ioctl) panic: from debugger cpuid = 0 Uptime: 21s Physical memory: 495 MB Dumping 55 MB: 40 24 8 -- //Monthadar Al Jaberi ___ freebsd-virtualization@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-virtualization To unsubscribe, send any mail to freebsd-virtualization-unsubscr...@freebsd.org
Re: simulating wireless device (if_alloc panic, VirtualBox, VIMAGE)
ok here's how it works.. any place you access a V_xxx variable you need to have the current vnet set. so somewhere in your code path to get to that point you have to have done CURVNET_SET() and after you have finised on the way out you should do CURVNET_RESTORE(). you can get the vnet from several places: 1/ as shown below, you can get it from any thread's cred if teh running thread is part of a process in the jail in question. 2/ if you have an ifp pointer, you can use ifp-vnet . I think that's right, it's been a while... 3/ I believe though I may be wrong (I may be thinking of multi FIBS) that it maybe in the socket structure too but don't trust me on that one.. check it. if, like in a timer thread you have access to NONE of those, you have several choices.. 1/ the caller of the timer may have given you indirect access to it in the arg. 2/ maybe you juaast have to interate through all the vimages.. to do whatever it is that you do (that happens in some protocols) On 2/1/11 11:04 AM, Monthadar Al Jaberi wrote: On Tue, Feb 1, 2011 at 6:25 PM, Julian Elischerjul...@freebsd.org wrote: On 2/1/11 8:40 AM, Monthadar Al Jaberi wrote: Hi, I hope I am on the write place, second try... I have written a module that loads fake wifi devices (wtap?) and distributes packets between them. For now I use route command to route packets between them from upper layers (TCP,...). I want to take it to next step and create jails with VNET. I started reading Julian Elischer's Vimage: what is it? and he says that if I am writing hardware drivers I dont need to make any changes when I enable VIMAGE option on the kernel, because each one will have their own stack. I can give a more detailed explanation on how my module works. But for now I get a panic when calling if_alloc() when using option VIMAGE. Thank you, while this was true to some extent it i snot 100% true now. during allocation we now try to have separate interface indexes per vimage which means that the setup routines do need to know the current vnet. so I cant call if_alloc directly? it looks like wtap_ioctl or wtap_attach should have the following: (copied from the tun driver) this should not be needed from real hardware based drivers as far as I can tell. CURVNET_SET(CRED_TO_VNET(cred)); /* find any existing device, or allocate new unit number */ i = clone_create(tunclones,tun_cdevsw,u, dev, 0); [blah] if_clone_create(name, namelen, NULL); CURVNET_RESTORE(); My wtap is based on ath driver code (if_ath.c) which should look like a real device right? if_ath.c is not using VNET, as far as I can tell Currently my module creates a couple of wtaps, which I then create a corresponding wlan. These wtaps are interconnected together, so no out world yet... so I dont have struct cdev *dev Basic idea is my module have a main queue (simulating air) and each wtap have a rx_task which sends packets up to higher layers, plus callout timer for generation beacons... I will try to use CURVET_SET(...) tomo My setup: FreeBSD Current 201010 guest on VirtualBox on Ubuntu 10.04. Kernel page fault with the following non-sleepable locks held: exclusive rw ifnet_rw (ifnet_rw) r = 0 (0xc0fc8284) locked @ /usr/src/sys/net/if.c:414 KDB: stack backtrace: db_trace_self_wrapper(c0cf3cdb,1,0,0,0,...) at db_trace_self_wrapper+0x26 kdb_backtrace(19e,1,,c0f9b194,c2fc9a1c,...) at kdb_backtrace+0x2a _witness_debugger(c0cf6408,c2fc9a30,4,1,0,...) at _witness_debugger+0x25 witness_warn(5,0,c0d2c479,3,c4070d48,...) at witness_warn+0x1fe trap(c2fc9abc) at trap+0x195 calltrap() at calltrap+0x6 --- trap 0xc, eip = 0xc0970999, esp = 0xc2fc9afc, ebp = 0xc2fc9b1c --- ifindex_alloc_locked(c0d003cf,c2fc9b36,19e,19e,c15ab714,...) at ifindex_alloc_locked+0x19 if_alloc(47,c4085a16,3,c0de9614,c32aa780,...) at if_alloc+0x85 wtap_attach(c31a7800,c40857c0,0,4,0,...) at wtap_attach+0x29 new_wtap(c32aa780,0,c2fc9bf0,c083ac9b,c3cbb200,...) at new_wtap+0x9b wtap_ioctl(c3cbb200,80045701,c31edaa0,1,c3f90b40,...) at wtap_ioctl+0x36 devfs_ioctl_f(c3cfe3b8,80045701,c31edaa0,c3185d00,c3f90b40,...) at devfs_ioctl_f+0x10b kern_ioctl(c3f90b40,3,80045701,c31edaa0,fc9cec,...) at kern_ioctl+0x20d ioctl(c3f90b40,c2fc9cec,c2fc9d28,c0cf5783,0,...) at ioctl+0x134 syscallenter(c3f90b40,c2fc9ce4,c2fc9ce4,0,0,...) at syscallenter+0x263 syscall(c2fc9d28) at syscall+0x34 Xint0x80_syscall() at Xint0x80_syscall+0x21 --- syscall (54, FreeBSD ELF32, ioctl), eip = 0x28181203, esp = 0xbfbfec3c, ebp = 0xbfbfec58 --- Fatal trap 12: page fault while in kernel mode cpuid = 0; apic id = 00 fault virtual address = 0x18 fault code = supervisor read, page not present instruction pointer = 0x20:0xc0970999 stack pointer = 0x28:0xc2fc9afc frame pointer = 0x28:0xc2fc9b1c code segment= base 0x0, limit 0xf, type 0x1b = DPL 0, pres 1, def32 1, gran 1 processor eflags=
