W dniu 18 czerwca 2011 14:03 użytkownik Pekka Paalanen <pq@xxxxxx> napisał: > Maybe the driver is doing a 16-bit wide access, and happens to > store something else in the other 16/48 bits of RAX? OK, attached is updated version of my patch. I think we can get some clue from dmesgs with this patch applied. My system (working): [ 74.472502] mmiotrace: ZAJEC: overwriting 0x27 with 0xFFFF [ 74.472511] mmiotrace: [ZAJEC] opcode is 0x8B [ 74.472515] mmiotrace: [ZAJEC] prf info: shorted:1; enlarged:0, rexr:0, rex:0 [ 74.472517] mmiotrace: [ZAJEC] register is 0x0 [ 74.472520] mmiotrace: [ZAJEC] overwritting 2-byte value 0x0514 with 0xFFFF [ 74.472523] mmiotrace: [ZAJEC] overwritting resulted in 0xFFFF [ 74.487081] mmiotrace: ZAJEC: overwriting 0x20 with 0xFFFF [ 74.487086] mmiotrace: [ZAJEC] opcode is 0x8B [ 74.487089] mmiotrace: [ZAJEC] prf info: shorted:1; enlarged:0, rexr:0, rex:0 [ 74.487092] mmiotrace: [ZAJEC] register is 0x0 [ 74.487095] mmiotrace: [ZAJEC] overwritting 2-byte value 0x427E with 0xFFFF [ 74.487097] mmiotrace: [ZAJEC] overwritting resulted in 0xFFFF MacBook (with real overwritting commenet out!): [ 228.248715] mmiotrace: ZAJEC: overwriting 0x810 with 0xFFFF [ 228.254227] mmiotrace: [ZAJEC] opcode is 0xB70F [ 228.259784] mmiotrace: [ZAJEC] prf info: shorted:0; enlarged:0, rexr:0, rex:0 [ 228.265399] mmiotrace: [ZAJEC] register is 0x0 [ 228.270955] mmiotrace: [ZAJEC] overwritting 4-byte value 0x00000000 with 0xFFFF [ 228.276597] mmiotrace: [ZAJEC] overwritting resulted in 0x00000000 [ 228.284284] mmiotrace: ZAJEC: overwriting 0x810 with 0xFFFF [ 228.289818] mmiotrace: [ZAJEC] opcode is 0xB70F [ 228.295250] mmiotrace: [ZAJEC] prf info: shorted:0; enlarged:0, rexr:0, rex:0 [ 228.300838] mmiotrace: [ZAJEC] register is 0x0 [ 228.306339] mmiotrace: [ZAJEC] overwritting 4-byte value 0x00000000 with 0xFFFF [ 228.311905] mmiotrace: [ZAJEC] overwritting resulted in 0x00000000 It's 2-byte vs. 4-byte. I suspect this can be the source of our problem. Writing u16 0xFFFF value as u32 write. -- Rafał
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mmio.debugging.patch
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