Description of problem: from gozen's report in https://bugzilla.redhat.com/show_bug.cgi?id=438878#c8 : There are some issues with -42 , I can't even get this to be tested. Here are some backtraces from dmesg: BUG: scheduling with irqs disabled: auditd/0x00000000/12737 caller is rt_spin_lock_slowlock+0xcf/0x14f Pid: 12737, comm: auditd Not tainted 2.6.24.4-42.el5rt #1 [<c0633b59>] schedule+0x8e/0x114 [<c06343ef>] rt_spin_lock_slowlock+0xcf/0x14f [<c0634a65>] __rt_spin_lock+0x4c/0x4e [<c0634a6f>] rt_spin_lock+0x8/0xa [<c04770bf>] page_address+0x4d/0x80 [<c047730d>] kmap_high+0xf0/0x463 [<c0403226>] ? __switch_to+0xa3/0x125 [<c042a515>] ? finish_task_switch+0x29/0xc4 [<c042c6cd>] ? __wake_up+0x34/0x4f [<c0477191>] ? kunmap_high+0x9f/0xa1 [<c0424140>] ? kunmap+0x52/0x54 [<c0424180>] kmap+0x3e/0x49 [<c0421398>] kmap_atomic_func+0x12/0x15 [<c0423802>] gup_pte_range+0x4f/0x135 [<c0423a86>] fast_gup+0x19e/0x264 [<c0449c96>] get_futex_key+0x70/0xa2 [<c044b1e5>] do_futex+0x383/0xa4b [<c048e0bd>] ? do_readv_writev+0x16d/0x178 [<c044b994>] sys_futex+0xe7/0xfa [<c048e5d8>] ? sys_writev+0x58/0x8f [<c0404226>] syscall_call+0x7/0xb ======================= WARNING: at arch/x86/kernel/smp_32.c:580 native_smp_call_function_mask() Pid: 13593, comm: automount Not tainted 2.6.24.4-42.el5rt #1 [<c0419d61>] ? do_flush_tlb_all+0x0/0x3f [<c0419f4e>] native_smp_call_function_mask+0x4c/0x12a [<c0419d61>] ? do_flush_tlb_all+0x0/0x3f [<c0476f78>] ? __set_page_address+0x8b/0x95 [<c0419d61>] ? do_flush_tlb_all+0x0/0x3f [<c0419d61>] ? do_flush_tlb_all+0x0/0x3f [<c041b4e5>] smp_call_function+0x1e/0x22 [<c0434059>] on_each_cpu+0x24/0x5c [<c0419c75>] flush_tlb_all+0x1e/0x20 [<c04774ba>] kmap_high+0x29d/0x463 [<c0424180>] kmap+0x3e/0x49 [<c0421398>] kmap_atomic_func+0x12/0x15 [<c0423802>] gup_pte_range+0x4f/0x135 [<c047bb7e>] ? handle_mm_fault+0xb7a/0xbb3 [<c0423a86>] fast_gup+0x19e/0x264 [<c0449c96>] get_futex_key+0x70/0xa2 [<c044a302>] futex_wake+0x38/0xbe [<c044aee7>] do_futex+0x85/0xa4b [<c0493d0a>] ? pipe_write+0x36f/0x3c4 [<c046fcf8>] ? __pagevec_free+0x17/0x1e [<c048d9fb>] ? do_sync_write+0xc5/0x102 [<c044b994>] sys_futex+0xe7/0xfa [<c0468c99>] ? __delayacct_add_tsk+0x205/0x210 [<c042cdd0>] mm_release+0x84/0x8b [<c0430c01>] exit_mm+0x15/0xfd [<c0432128>] do_exit+0x213/0x716 [<c04070a8>] ? do_syscall_trace+0x14c/0x198 [<c04326bb>] complete_and_exit+0x0/0x16 [<c0404226>] syscall_call+0x7/0xb ======================= Version-Release number of selected component (if applicable): kernel-rt-2.6.24.4-42.el5rt How reproducible: reliably for gozen at least Steps to Reproduce: Try to boot the 32 bit kernel. Actual results: crash with the backtrace Expected results: should boot without problems Additional info: No problems with x86_64 reported so far. Only 32 bit machines seem to be affected. Recently futex-fast_gup was merged in kernel-rt and fast_gup can be seen in the stack trace, so it seems to be the primary suspect.
Ok so a little bit more info.. I tested kernel-rt-2.6.24.4-{39,41,42} with same results. However kernel-rt-2.6.24.4-37 seems to boot and run sane though.
is this the bug that requires a HIGHPTE fix?
I believe this should be fixed in -47. When Gurhan tests bug 438878, he'll know if this one is fixed too.
-47 kernel boots fine.
closing