Responding to my self to help others... > On Oct 8, 2016, at 08:14, Jean-Francois Dagenais <jeff.dagenais@xxxxxxxxx> wrote: > > > <3>[ 191.166625] Padding ddca2f60: 00 00 00 00 00 00 00 00 01 00 00 00 fc 03 00 00 ................ > <3>[ 191.166669] Padding ddca2f70: 21 c4 ff ff 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a !...ZZZZZZZZZZZZ > <3>[ 191.166713] Padding ddca2f80: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ > <3>[ 191.166755] Padding ddca2f90: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ > <3>[ 191.166798] Padding ddca2fa0: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ > <3>[ 191.166841] Padding ddca2fb0: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ > <3>[ 191.166883] Padding ddca2fc0: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ > <3>[ 191.166926] Padding ddca2fd0: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ > <3>[ 191.166969] Padding ddca2fe0: 5a 5a 5a 5a 00 00 5c 1f ZZZZ..\. > <3>[ 191.167011] FIX vm_area_struct: Restoring 0xddca2f60-0xddca2fe7=0x5a > Found the bug. It was in xilinx_cdma.c where the tx descriptor allocator was mistakenly trying to link the previous HW SG struct which didn't exist with the current one being created. It was using list_first_entry on a freshly initialized list_head (pointing to itself), so container_of was backing from another struct type into the wrong struct. The 0x1f5c0000 was the physical address of the HW SG descriptor written 4 bytes below the transaction struct found at VM0xddca3000. > > I'd like to stop messing around and debug this like a pro. What tools and/or > keywords and/or technique should I know and use here? Anyway, are there any tools worth sharing? For example a tool that could absorb the huge owner tracing output so we can later "data mine" who may have owned which part of memory? -- 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