[Crash-utility] Re: [Patch] Fix dev -p command for systems with virtual devices

Hi Dave Running 'dev -p' command on PowerPC systems with virtual devices (ie no real PCI devices) fails with the following message: dev: invalid kernel virtual address: 98 type: "pci bus number" It should instead report that there are no _real_ PCI devices to list. The following patch addresses this issue. Currently it just prints a message letting the user know of the absence of pci devices, but it might be a good idea to list down the virtual devices present in the system in such cases. I am working on a patch for that too, probably will discuss that on another thread. Please provide your comments/suggestions. Thanks Rachita

On PowerPC machines configured with virtual devices(VIO) it is possible that there are no _real_ PCI devices. Hence it is reasonable that 'dev -p' would not list anything. This patch identifies such cases and displays a message appropriately. Signed-off-by: Rachita Kothiyal <rachita(a)in.ibm.com&gt; --- dev.c | 30 +++++++++++++++++++++++++++--- 1 files changed, 27 insertions(+), 3 deletions(-) diff -puN dev.c~fix-vio-pci-device dev.c --- crash-4.0-3.9/dev.c~fix-vio-pci-device 2006-12-22 13:32:02.737262096 +0530 +++ crash-4.0-3.9-rachita/dev.c 2006-12-22 13:48:44.984897296 +0530 @@ -1955,13 +1955,11 @@ do_pci(void) unsigned int class; unsigned short device, vendor; unsigned char busno; - ulong *devlist, bus, devfn, tmp; + ulong *devlist, bus, devfn, tmp, prev, next; char buf1[BUFSIZE]; char buf2[BUFSIZE]; char buf3[BUFSIZE]; - fprintf(fp, "%s BU:SL.FN CLASS: VENDOR-DEVICE\n", - mkstring(buf1, VADDR_PRLEN, CENTER|LJUST, "PCI_DEV")); BZERO(&pcilist_data, sizeof(struct list_data)); @@ -1972,11 +1970,34 @@ do_pci(void) FAULT_ON_ERROR); pcilist_data.end = symbol_value("pci_devices"); pcilist_data.list_head_offset = OFFSET(pci_dev_global_list); + readmem(symbol_value("pci_devices") + OFFSET(list_head_prev), + KVADDR, &prev, sizeof(void *), "list head prev", + FAULT_ON_ERROR); + /* + * Check if this system does not have any PCI devices. + * Possible on PowerPC machines with VIO configured. + */ + if ((pcilist_data.start == pcilist_data.end) && + (prev == pcilist_data.end)) { + fprintf(fp, "No PCI devices found on this system.\n"); + return; + } } else { get_symbol_data("pci_devices", sizeof(void *), &pcilist_data.start); pcilist_data.member_offset = OFFSET(pci_dev_next); + /* + * Check if this system does not have any PCI devices. + * Possible on PowerPC machines with VIO configured. + */ + readmem(pcilist_data.start + pcilist_data.member_offset, + KVADDR, &next, sizeof(void *), "pci dev next", + FAULT_ON_ERROR); + if (!next) { + fprintf(fp, "No PCI devices found on this system.\n"); + return; + } } hq_open(); @@ -1985,6 +2006,9 @@ do_pci(void) devcnt = retrieve_list(devlist, devcnt); hq_close(); + fprintf(fp, "%s BU:SL.FN CLASS: VENDOR-DEVICE\n", + mkstring(buf1, VADDR_PRLEN, CENTER|LJUST, "PCI_DEV")); + for (i = 0; i < devcnt; i++) { /* _