On Thu, Oct 24, 2013 at 09:07:30PM +0100, Aaro Koskinen wrote: > Hi, Hello, [adding Catalin and Simon] > I was trying to debug kernel crashes on Marvell Kirkwood (openrd) > when upgrading from GCC 4.7.3 -> GCC 4.8.2. So I enabled most of the > kernel debug options. However, I noticed that already when compiled with > GCC 4.7.3 kernel crashes consistently at boot when DEBUG_VM is enabled > (without it there are no issues with 4.7.3). See below for the boot/crash > log & kernel config. Ok, but this doesn't seem to be related to GCC. [...] > [ 26.694345] ata2: link is slow to respond, please be patient (ready=0) > [ 31.194346] ata2: SRST failed (errno=-16) > [ 31.754426] ata2: SATA link up 3.0 Gbps (SStatus 123 SControl F300) > [ 31.834619] ata2.00: ATA-6: eSATA-2 WD5000AAKX-00ERMA0, 15.01H15, max UDMA/133 > [ 31.899627] ata2.00: 976773168 sectors, multi 0: LBA48 > [ 31.994458] ata2.00: configured for UDMA/133 > [ 32.075306] ------------[ cut here ]------------ > [ 32.136256] kernel BUG at mm/util.c:390! > [ 32.195446] Internal error: Oops - BUG: 0 [#1] PREEMPT ARM > [ 32.255893] Modules linked in: > [ 32.313109] CPU: 0 PID: 12 Comm: kworker/u2:1 Not tainted 3.12.0-rc6-openrd-los.git-1836ad9-dirty #3 > [ 32.435821] Workqueue: events_unbound async_run_entry_fn > [ 32.498701] task: df854700 ti: df8a8000 task.ti: df8a8000 > [ 32.561662] PC is at page_mapping+0x48/0x50 > [ 32.622764] LR is at flush_kernel_dcache_page+0x14/0x98 > [ 32.685421] pc : [<c00923c4>] lr : [<c0010dd8>] psr: 20000093 > [ 32.685421] sp : df8a99f8 ip : df8a9a08 fp : df8a9a04 > [ 32.812754] r10: 60000093 r9 : df8a9c24 r8 : 00000024 > [ 32.874269] r7 : 00000000 r6 : c0a3cd0c r5 : 00001000 r4 : c0e2732c > [ 32.936395] r3 : 00000000 r2 : 00000080 r1 : 00000564 r0 : c0e2732c > [ 32.996978] Flags: nzCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment kernel > [ 33.059012] Control: 0005317f Table: 1a8dc000 DAC: 00000017 > [ 33.119473] Process kworker/u2:1 (pid: 12, stack limit = 0xdf8a81c0) The BUG is because page_mapping is being given a slab page... > [ 36.477203] Backtrace: > [ 36.535603] [<c009237c>] (page_mapping+0x0/0x50) from [<c0010dd8>] (flush_kernel_dcache_page+0x14/0x98) > [ 36.661070] [<c0010dc4>] (flush_kernel_dcache_page+0x0/0x98) from [<c0172b60>] (sg_miter_stop+0xc8/0x10c) > [ 36.792813] r4:df8a9a64 r3:00000003 > [ 36.857524] [<c0172a98>] (sg_miter_stop+0x0/0x10c) from [<c0172f20>] (sg_miter_next+0x14/0x13c) ... assumedly for scatter/gather DMA. How is your block driver allocating its buffers? If you're using the DMA API, I can't see how this would happen. Will -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>