(switched to email. Please respond via emailed reply-to-all, not via the bugzilla web interface).
On Wed, 9 Sep 2009 15:09:15 GMT bugzilla-dae...@bugzilla.kernel.org wrote: > http://bugzilla.kernel.org/show_bug.cgi?id=14148 > > Summary: kernel panic: do_wp_page assert_pte_locked failed when > DEBUG_VM > Product: Platform Specific/Hardware > Version: 2.5 > Kernel Version: 2.6.31-rc3, 2.6.31-rc9-git2 > Platform: All > OS/Version: Linux > Tree: Mainline > Status: NEW > Severity: normal > Priority: P1 > Component: PPC-32 > AssignedTo: platform_ppc...@kernel-bugs.osdl.org > ReportedBy: wan...@lzu.edu.cn > Regression: Yes > > > Created an attachment (id=23049) > --> (http://bugzilla.kernel.org/attachment.cgi?id=23049) > problematic config file for mpc8548cds > > powerpc mpc8548cds (I only have this board on hand) will kernel panic if > DEBUG_VM (kernel hacking) is enabled due to assertion failed in function > do_wp_page(). I think it highly possible for other ppc boards like 44x have > the > same problem too, but I don't have the board. > > here is the full log from power up (after u-boot). and the attachment is > related .config, NOTE the kernel boot successfully if CONFIG_DEBUG_VM is not > enabled. > > host system is gentoo, the gcc (powerpc-unknown-linux-gnu-gcc) is build by > gentoo crossdev, version 4.4.1, (cross) glibc is 2.9, (cross) binutils is > 2.19.1, (cross) kernel headers is 2.6.30. target (mpc8548cds) root filesystem > is also gentoo (200907xx, extracted from stage3 tarball). > > I have running similar test on x86 using qemu (0.10.6, +kvm), the result seems > OK, especially x86 pass all lock api test suite. First question: > [10611.192802] ------------[ cut here ]------------ > [10611.197409] Kernel BUG at c0014d70 [verbose debug info unavailable] Why did we not get the file-n-line? That's iritating. Oh, CONFIG_DEBUG_BUGVERBOSE=n. Don't do that. We should make that thing harder to get at, to stop people shooting our feet off. > [10611.203660] Oops: Exception in kernel mode, sig: 5 [#1] > [10611.208866] PREEMPT MPC85xx CDS > [10611.211997] Modules linked in: > [10611.215040] NIP: c0014d70 LR: c0014eb4 CTR: 00000002 > [10611.219988] REGS: cf82db40 TRAP: 0700 Not tainted (2.6.31-rc3) > [10611.226061] MSR: 00029000 <EE,ME,CE> CR: 88448044 XER: 20000000 > [10611.232162] TASK = cf828000[1] 'init' THREAD: cf82c000 > [10611.237108] GPR00: 00000001 cf82dbf0 cf828000 cf9781c0 bf8031d8 cf9f400c > 0057902f 00000001 > [10611.245471] GPR08: cf978200 cf9f4000 00000002 00000000 28448042 1001b0b0 > 00000001 cf88ee00 > [10611.253833] GPR16: c05c0000 bf8031d8 00000002 10000000 48000000 00000001 > 00000008 c05ecf20 > [10611.262196] GPR24: 0057902b 0057902f cf82c000 00000000 cf9f400c 00000001 > bf8031d8 cf98b000 > [10611.270749] NIP [c0014d70] assert_pte_locked+0x3c/0x44 > [10611.275872] LR [c0014eb4] ptep_set_access_flags+0xa8/0xf4 > [10611.281252] Call Trace: > [10611.283687] [cf82dbf0] [bf8031d8] 0xbf8031d8 (unreliable) > [10611.289079] [cf82dc10] [c008e87c] do_wp_page+0xf8/0x82c > [10611.294292] [cf82dc60] [c0014770] do_page_fault+0x2c0/0x480 > [10611.299851] [cf82dd10] [c0011078] handle_page_fault+0xc/0x80 > [10611.305504] [cf82ddd0] [c00f2b4c] load_elf_binary+0x8a8/0x121c > [10611.311325] [cf82de50] [c00af418] search_binary_handler+0x144/0x37c > [10611.317578] [cf82dea0] [c00b0bc8] do_execve+0x270/0x2c8 > [10611.322794] [cf82dee0] [c0008754] sys_execve+0x68/0xa4 > [10611.327919] [cf82df00] [c0010c38] ret_from_syscall+0x0/0x3c > [10611.333482] [cf82dfc0] [c00b9350] sys_dup+0x38/0x78 > [10611.338349] [cf82dfd0] [c0002030] init_post+0x94/0x108 > [10611.343478] [cf82dfe0] [c054c234] kernel_init+0x114/0x130 > [10611.348865] [cf82dff0] [c00109b8] kernel_thread+0x4c/0x68 > [10611.354249] Instruction dump: > [10611.357206] 4d9e0020 38000000 0f000000 0f000000 81230024 5480653a 7c09002e > 54090027 > [10611.364959] 7c000026 54001ffe 0f000000 38000001 <0f000000> 4e800020 > 7c0802a6 > 9421fff0 > [10611.372887] ---[ end trace 0cda2392272f221a ]--- So do_wp_page() called ptep_set_access_flags(). If CONFIG_DEBUG_VM=y, powerpc's ptep_set_access_flags() will call arch/powerpc/mm/pgtable.c:assert_pte_locked(). Because of the lack of file-n-line info it is unclear which of those many assertions triggered. It looks like BUG_ON(!pmd_present(*pmd)). Perhaps. Please set CONFIG_DEBUG_BUGVERBOSE=y in your .config and then tell us (via emailed reply-to-all) which line in arch/powerpc/mm/pgtable.c triggered the BUG. Please actually quote that line, or tell us exactly which kernel version you're using so we can see which line it was in the source code. Thanks. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
