On Wed, 20 Apr 2022 at 13:01, Ard Biesheuvel <ardb@xxxxxxxxxx> wrote: > > On Tue, 19 Apr 2022 at 12:59, Naresh Kamboju <naresh.kamboju@xxxxxxxxxx> wrote: > > > > Linux next 20220419 boot failed on arm architecture qemu_arm and BeagleBoard > > x15 device. > > > > kernel crash log from x15: > > ----------------- > > [ 6.866516] 8<--- cut here --- > > [ 6.869598] Unable to handle kernel paging request at virtual > > address f000e62c > > [ 6.876861] [f000e62c] *pgd=82935811, *pte=00000000, *ppte=00000000 > > [ 6.883209] Internal error: Oops: 807 [#3] SMP ARM > > [ 6.888000] Modules linked in: > > [ 6.891082] CPU: 1 PID: 1 Comm: swapper/0 Tainted: G D W > > 5.18.0-rc3-next-20220419 #1 > > [ 6.899993] Hardware name: Generic DRA74X (Flattened Device Tree) > > [ 6.906127] PC is at cpu_ca15_set_pte_ext+0x4c/0x58 > > [ 6.911041] LR is at handle_mm_fault+0x60c/0xed0 > > [ 6.915679] pc : [<c031f26c>] lr : [<c04cfeb8>] psr: 40000013 > > [ 6.921966] sp : f000dde8 ip : f000de44 fp : a0000013 > > [ 6.927215] r10: 00000000 r9 : 00000000 r8 : c1e95194 > > [ 6.932464] r7 : c3c95000 r6 : befffff1 r5 : 00000081 r4 : c29d8000 > > [ 6.939025] r3 : 00000000 r2 : 00000000 r1 : 00000040 r0 : f000de2c > > [ 6.945587] Flags: nZcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none > > [ 6.952758] Control: 10c5387d Table: 8020406a DAC: 00000051 > > [ 6.958526] Register r0 information: 2-page vmalloc region starting > > at 0xf000c000 allocated at kernel_clone+0x94/0x3b0 > > [ 6.969299] Register r1 information: non-paged memory > > [ 6.974365] Register r2 information: NULL pointer > > [ 6.979095] Register r3 information: NULL pointer > > [ 6.983825] Register r4 information: slab task_struct start > > c29d8000 pointer offset 0 > > [ 6.991729] Register r5 information: non-paged memory > > [ 6.996795] Register r6 information: non-paged memory > > [ 7.001861] Register r7 information: slab vm_area_struct start > > c3c95000 pointer offset 0 > > [ 7.010009] Register r8 information: non-slab/vmalloc memory > > [ 7.015716] Register r9 information: NULL pointer > > [ 7.020446] Register r10 information: NULL pointer > > [ 7.025238] Register r11 information: non-paged memory > > [ 7.030426] Register r12 information: 2-page vmalloc region > > starting at 0xf000c000 allocated at kernel_clone+0x94/0x3b0 > > [ 7.041259] Process swapper/0 (pid: 1, stack limit = 0xfaff0077) > > [ 7.047302] Stack: (0xf000dde8 to 0xf000e000) > > [ 7.051696] dde0: c29d8000 00000cc0 c20a1108 > > c2065fa0 c1e09f50 b6db6db7 > > [ 7.059906] de00: c195bf0c 17c0f572 c29d8000 c3c95000 00000cc0 > > 000befff befff000 befffff1 > > [ 7.068115] de20: 00000081 c3c3afb8 c3c3afb8 00000000 00000000 > > 00000000 00000000 00000000 > > [ 7.076324] de40: 00000000 17c0f572 befff000 c3c95000 00002017 > > befffff1 00002017 00002fb8 > > [ 7.084564] de60: c2d04000 00000081 c29d8000 c04c6790 c20d01d4 > > 00000000 00000001 c20ce440 > > [ 7.092773] de80: c1e10bcc fffff000 00000000 c2a45680 eeb33cc0 > > c29d8000 00000000 c2d04000 > > [ 7.100982] dea0: befffff1 f000df18 00000000 00002017 c20661a0 > > c04c77e8 f000df18 00000000 > > [ 7.109222] dec0: 00000000 c1d95c40 00000002 c20661e0 00000000 > > 00000001 00000000 c04c7ad0 > > [ 7.117431] dee0: 00000011 c2d02a00 00000001 befffff1 c29d8000 > > 00000000 00000011 c2a30010 > > [ 7.125640] df00: c29d8000 c0524c24 f000df18 00000000 00000000 > > 2cd9e000 c1d95c40 17c0f572 > > [ 7.133850] df20: 00000000 c2d02a00 0000000b 00000ffc 00000000 > > befffff1 00000000 c0524f74 > > [ 7.142089] df40: c1e0e394 c2d02a00 c209a71c 38e38e39 c29d8000 > > bee00008 c2d02a00 c2a30000 > > [ 7.150299] df60: c1e0e394 c1e0e420 00000000 00000000 00000000 > > c05266bc c209a000 c1944c60 > > [ 7.158508] df80: 00000000 00000000 00000000 c129d2b4 c209a000 > > c1e0e394 00000000 c12b5600 > > [ 7.166748] dfa0: 00000000 c12b5518 00000000 c0300168 00000000 > > 00000000 00000000 00000000 > > [ 7.174957] dfc0: 00000000 00000000 00000000 00000000 00000000 > > 00000000 00000000 00000000 > > [ 7.183166] dfe0: 00000000 00000000 00000000 00000000 00000013 > > 00000000 00000000 00000000 > > [ 7.191406] Code: 13110001 12211b02 13110b02 03a03000 (e5a03800) > > This decodes to > > 0: 13110001 tstne r1, #1 > 4: 12211b02 eorne r1, r1, #2048 ; 0x800 > 8: 13110b02 tstne r1, #2048 ; 0x800 > c: 03a03000 moveq r3, #0 > 10:* e5a03800 str r3, [r0, #2048]! ; 0x800 <-- trapping instruction > > and R0 points into the stack. So we are updating a PTE that is located > on the stack rather than in a page table somewhere, which seems very > odd. However, this could be a latent bug that got uncovered by the > VMAP stacks changes. > > Unfortunately, the vmlinux.xz file I downloaded from the link below > seems to be different from the one that produced the crash, given that > the LR address of c04cfeb8 does not seem to correspond with > handle_mm_fault+0x60c/0xed0. > Can you please double check the artifacts? You can find the vmlinux.xz for the trace log I have pasted. vmlinux.xz : https://builds.tuxbuild.com/280TS8MuM6sYWk5aUtrvWIw0RQ7/vmlinux.xz artifact-location: https://builds.tuxbuild.com/280TS8MuM6sYWk5aUtrvWIw0RQ7 - Naresh
