RE: Machine check exception. 2.6.20 powerpc tree.
Hi Kumar The address we are trying to access corresponds to a mapped device in the PCI space Attached some additional debugging information (we have instrumented the kernel) Thanks jorge INFO [_probe]: Found Device [irq=58] INFO [_open]: device opened with irq 58 INFO [_read]: waiting for interrupt INFO [_intr]: ISR 58 PCI1: Error! ERR_DETECT=0040, ATTR=00516001, addr=80020034, data=0005 machine_check_exception: task my_process, MCSR=0x10008, NIP=0x10153530 Machine check in user mode. Caused by (from MCSR=10008): Guarded Load or Cache-Inhibited stwcx. Bus - Read Data Bus Error Call Trace: [C7355EF0] [C0006E64] show_stack+0x48/0x19c (unreliable) [C7355F20] [C000C04C] machine_check_exception+0x294/0x484 [C7355F40] [C000E48C] ret_from_mcheck_exc+0x0/0xe0 cat /proc/cpuinfo processor : 0 cpu : e500v2 clock : 799.50MHz revision: 2.0 (pvr 8021 0020) bogomips: 99.84 timebase: 49968750 platform: MPC85xx CDS Vendor : Freescale Semiconductor Machine : MPC85xx CDS (0xff) PVR : 0x80210020 SVR : 0x80390220 PLL setting : 0x4 Memory : 256 MB LAW 1 : , 2000 - DDR SDRAM LAW 2 : 8000, 1000 - PCI1 LAW 3 : 9000, 1000 - PCI2 LAW 4 : a000, 1000 - PCI Express LAW 5 : e100, 0100 - PCI1 LAW 6 : e200, 0100 - PCI2 LAW 7 : e300, 0100 - PCI Express LAW 8 : f000, 1000 - Local bus DDR 0 : , 2000 - 2/14/10 addr bits PCI1 Out_1 : 8000, 1000 - Mem: 8000 PCI1 Out_2 : e100, 0100 - I/O: PCI2 Out_1 : 9000, 1000 - Mem: 9000 PCI2 Out_2 : e200, 0100 - I/O: PCI3 Out_1 : a000, 1000 - Mem: a000 PCI3 Out_2 : e300, 0100 - I/O: PCI1 In_1 : , 2000 (Internal,R:snoop,W:snoop) - PF PCI2 In_1 : , 2000 (Internal,R:snoop,W:snoop) - PF PCI3 In_1 : , 2000 (Internal,R:snoop,W:snoop) - PF __ -Original Message- From: Kumar Gala [mailto:[EMAIL PROTECTED] Sent: 17 July 2007 17:29 To: Ramirez-Ortiz, Jorge Cc: linuxppc-embedded@ozlabs.org Subject: Re: Machine check exception. 2.6.20 powerpc tree. On Jul 17, 2007, at 9:21 AM, Ramirez-Ortiz, Jorge wrote: Running our multithreaded application on ppc8548 (E500 core) generates a machine check exception when trying to access some ASIC's registers mapped on the PCI space (This application maps a PCI device to access its registers) machine_check_exception: task my_process, MCSR=0x10008, NIP=0x10153530 Machine check in user mode. Caused by (from MCSR=10008): Guarded Load or Cache-Inhibited stwcx. Bus - Read Data Bus Error Here is the assembly dump of the region of code containing the offending instruction in user-space, with SRR0 pointing us at 0x10153530 when the exception is raised: 0x10153528 _ZN2vk7in_le32EPVKj+16:lwz r0,8(r31) 0x1015352c _ZN2vk7in_le32EPVKj+20:lwz r9,8(r31) 0x10153530 _ZN2vk7in_le32EPVKj+24:lwbrx r0,0,r0 0x10153534 _ZN2vk7in_le32EPVKj+28:twi 0,r0,0 0x10153538 _ZN2vk7in_le32EPVKj+32:isync Can you get the code to dump the value of r0. I'm wondering if you're really getting a read data bus error due to the fact that r0 is pointing to a PCI address that doesn't have a device that will respond. - k ___ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded
Re: Machine check exception. 2.6.20 powerpc tree.
On Jul 18, 2007, at 4:27 AM, Ramirez-Ortiz, Jorge wrote: Hi Kumar The address we are trying to access corresponds to a mapped device in the PCI space Attached some additional debugging information (we have instrumented the kernel) Thanks jorge INFO [_probe]: Found Device [irq=58] INFO [_open]: device opened with irq 58 INFO [_read]: waiting for interrupt INFO [_intr]: ISR 58 PCI1: Error! ERR_DETECT=0040, ATTR=00516001, addr=80020034, data=0005 So you are getting a master abort from the target. I think you need to look at your PCI device and see what's going on there. machine_check_exception: task my_process, MCSR=0x10008, NIP=0x10153530 Machine check in user mode. Caused by (from MCSR=10008): Guarded Load or Cache-Inhibited stwcx. Bus - Read Data Bus Error Call Trace: [C7355EF0] [C0006E64] show_stack+0x48/0x19c (unreliable) [C7355F20] [C000C04C] machine_check_exception+0x294/0x484 [C7355F40] [C000E48C] ret_from_mcheck_exc+0x0/0xe0 cat /proc/cpuinfo processor : 0 cpu : e500v2 clock : 799.50MHz revision: 2.0 (pvr 8021 0020) bogomips: 99.84 timebase: 49968750 platform: MPC85xx CDS Vendor : Freescale Semiconductor Machine : MPC85xx CDS (0xff) PVR : 0x80210020 SVR : 0x80390220 PLL setting : 0x4 Memory : 256 MB LAW 1 : , 2000 - DDR SDRAM LAW 2 : 8000, 1000 - PCI1 LAW 3 : 9000, 1000 - PCI2 LAW 4 : a000, 1000 - PCI Express LAW 5 : e100, 0100 - PCI1 LAW 6 : e200, 0100 - PCI2 LAW 7 : e300, 0100 - PCI Express LAW 8 : f000, 1000 - Local bus DDR 0 : , 2000 - 2/14/10 addr bits PCI1 Out_1 : 8000, 1000 - Mem: 8000 PCI1 Out_2 : e100, 0100 - I/O: PCI2 Out_1 : 9000, 1000 - Mem: 9000 PCI2 Out_2 : e200, 0100 - I/O: PCI3 Out_1 : a000, 1000 - Mem: a000 PCI3 Out_2 : e300, 0100 - I/O: PCI1 In_1 : , 2000 (Internal,R:snoop,W:snoop) - PF PCI2 In_1 : , 2000 (Internal,R:snoop,W:snoop) - PF PCI3 In_1 : , 2000 (Internal,R:snoop,W:snoop) - PF __ -Original Message- From: Kumar Gala [mailto:[EMAIL PROTECTED] Sent: 17 July 2007 17:29 To: Ramirez-Ortiz, Jorge Cc: linuxppc-embedded@ozlabs.org Subject: Re: Machine check exception. 2.6.20 powerpc tree. On Jul 17, 2007, at 9:21 AM, Ramirez-Ortiz, Jorge wrote: Running our multithreaded application on ppc8548 (E500 core) generates a machine check exception when trying to access some ASIC's registers mapped on the PCI space (This application maps a PCI device to access its registers) machine_check_exception: task my_process, MCSR=0x10008, NIP=0x10153530 Machine check in user mode. Caused by (from MCSR=10008): Guarded Load or Cache-Inhibited stwcx. Bus - Read Data Bus Error Here is the assembly dump of the region of code containing the offending instruction in user-space, with SRR0 pointing us at 0x10153530 when the exception is raised: 0x10153528 _ZN2vk7in_le32EPVKj+16:lwz r0,8(r31) 0x1015352c _ZN2vk7in_le32EPVKj+20:lwz r9,8(r31) 0x10153530 _ZN2vk7in_le32EPVKj+24:lwbrx r0,0,r0 0x10153534 _ZN2vk7in_le32EPVKj+28:twi 0,r0,0 0x10153538 _ZN2vk7in_le32EPVKj+32:isync Can you get the code to dump the value of r0. I'm wondering if you're really getting a read data bus error due to the fact that r0 is pointing to a PCI address that doesn't have a device that will respond. - k ___ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded
Machine check exception. 2.6.20 powerpc tree.
Running our multithreaded application on ppc8548 (E500 core) generates a machine check exception when trying to access some ASIC's registers mapped on the PCI space (This application maps a PCI device to access its registers) machine_check_exception: task my_process, MCSR=0x10008, NIP=0x10153530 Machine check in user mode. Caused by (from MCSR=10008): Guarded Load or Cache-Inhibited stwcx. Bus - Read Data Bus Error Here is the assembly dump of the region of code containing the offending instruction in user-space, with SRR0 pointing us at 0x10153530 when the exception is raised: 0x10153528 _ZN2vk7in_le32EPVKj+16:lwz r0,8(r31) 0x1015352c _ZN2vk7in_le32EPVKj+20:lwz r9,8(r31) 0x10153530 _ZN2vk7in_le32EPVKj+24:lwbrx r0,0,r0 0x10153534 _ZN2vk7in_le32EPVKj+28:twi 0,r0,0 0x10153538 _ZN2vk7in_le32EPVKj+32:isync All this is fully reproducible, the offending code is repeatedly the byte-reverse load within the (m)mapped PCI memory segment. The offset within the segment may vary, even if most of the hits seem to be taken when reading 0x20030-0x20034 offsets from 0x8000 PCI address space (which is mapped to the application via /dev/mem) /proc/pid/maps reports the following mappings to /dev/mem, with the first one being an ASIC on the PCI space whose registers we are trying to access, and the second one being system memory (this system memory is out of kernel visibility...we use 'mem=256M' as a kernel parameter...): 303a9000-304a9000 rw-s 8000 00:0c 2087 /dev/mem 304a9000-404a9000 rw-s 1000 00:0c 2087 /dev/mem Has anybody experienced something similar using a kernel based on a 2.6.20 powerpc tree? Many thanks jorge __ Jorge Ramirez-Ortiz ___ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded
Re: Machine check exception. 2.6.20 powerpc tree.
On Jul 17, 2007, at 9:21 AM, Ramirez-Ortiz, Jorge wrote: Running our multithreaded application on ppc8548 (E500 core) generates a machine check exception when trying to access some ASIC’s registers mapped on the PCI space (This application maps a PCI device to access its registers) machine_check_exception: task my_process, MCSR=0x10008, NIP=0x10153530 Machine check in user mode. Caused by (from MCSR=10008): Guarded Load or Cache-Inhibited stwcx. Bus - Read Data Bus Error Here is the assembly dump of the region of code containing the offending instruction in user-space, with SRR0 pointing us at 0x10153530 when the exception is raised: 0x10153528 _ZN2vk7in_le32EPVKj+16:lwz r0,8(r31) 0x1015352c _ZN2vk7in_le32EPVKj+20:lwz r9,8(r31) 0x10153530 _ZN2vk7in_le32EPVKj+24:lwbrx r0,0,r0 0x10153534 _ZN2vk7in_le32EPVKj+28:twi 0,r0,0 0x10153538 _ZN2vk7in_le32EPVKj+32:isync Can you get the code to dump the value of r0. I'm wondering if you're really getting a read data bus error due to the fact that r0 is pointing to a PCI address that doesn't have a device that will respond. - k ___ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded
