Re: [PATCH] Revert "net: pskb_trim_rcsum() and CHECKSUM_COMPLETE are friends"
From: Andreas Schwab
Date: Tue Jun 19 2018 - 15:11:01 EST
On Jun 18 2018, Eric Dumazet <eric.dumazet@xxxxxxxxx> wrote:
> DUMP_PREFIX_ADDRESS might give us more information (say alignment problem, or crossing page boundaries)
DUMP_PREFIX_ADDRESS is useless for that purpose.
Here are some samples of broken csums:
[ 853.849225] sungem: sungem wrong csum : 9886/07be, len 94 bytes, c0000001fa187e02
[ 853.849232] raw data: 00000000: 00 0d 93 43 81 62 18 d6 c7 51 b8 1c 08 00 45 10 ...C.b...Q....E.
[ 853.849235] raw data: 00000010: 00 4c cb a0 40 00 40 11 d9 97 c0 a8 0a 01 c0 a8 .L..@.@.........
[ 853.849237] raw data: 00000020: 0a 07 00 7b 00 7b 00 38 69 e1 1c 03 0c f7 00 00 ...{.{.8i.......
[ 853.849240] raw data: 00000030: 08 f0 00 00 15 f0 c0 35 67 67 de d3 ca c9 d9 5b .......5gg.....[
[ 853.849242] raw data: 00000040: 1f ff de d3 d2 86 8f 67 fa f2 de d3 d2 86 8f 38 .......g.......8
[ 853.849244] raw data: 00000050: 2f ff de d3 d2 86 8f 3b ff ff d1 93 bc 50 /......;.....P
[ 857.883052] sungem: sungem wrong csum : dbb4/c48f, len 94 bytes, c0000001fa185882
[ 857.883058] raw data: 00000000: 00 0d 93 43 81 62 18 d6 c7 51 b8 1c 08 00 45 00 ...C.b...Q....E.
[ 857.883070] raw data: 00000010: 00 4c a1 97 40 00 3a 11 ce ed d9 5b 2c 11 c0 a8 .L..@.:....[,...
[ 857.883080] raw data: 00000020: 0a 07 00 7b 00 7b 00 38 14 4b 24 02 06 ea 00 00 ...{.{.8.K$.....
[ 857.883085] raw data: 00000030: 00 0b 00 00 02 99 c0 a8 64 09 de d3 d2 5a 36 e4 ........d....Z6.
[ 857.883090] raw data: 00000040: bc f5 de d3 d2 8a 8f 2c 17 44 de d3 d2 8a 93 8b .......,.D......
[ 857.883094] raw data: 00000050: d7 b7 de d3 d2 8a 93 97 69 6e 39 7b d2 5a ........in9{.Z
[ 858.124689] sungem: sungem wrong csum : 1f4f/02d0, len 118 bytes, c0000001fa185602
[ 858.124700] raw data: 00000000: 00 0d 93 43 81 62 d4 3d 7e 4c 48 b7 86 dd 61 01 ...C.b.=~LH...a.
[ 858.124705] raw data: 00000010: 1e b1 00 3c 06 40 20 01 0a 62 17 11 88 01 00 00 ...<.@ ..b......
[ 858.124709] raw data: 00000020: 00 00 00 00 0a 38 20 01 0a 62 17 11 88 01 00 00 .....8 ..b......
[ 858.124714] raw data: 00000030: 00 00 00 00 00 07 94 b4 00 16 86 f5 29 e8 36 cb ............).6.
[ 858.124718] raw data: 00000040: 50 49 80 18 05 93 9a 53 00 00 01 01 08 0a 58 b2 PI.....S......X.
[ 858.124723] raw data: 00000050: de 54 61 5f 2f 3c 00 00 00 10 cc 08 55 f7 da 21 .Ta_/<......U..!
[ 858.124727] raw data: 00000060: f4 60 0a 6b 3c aa b9 b3 7e 61 10 b8 c2 be 9a 0b .`.k<...~a......
[ 858.124731] raw data: 00000070: c7 e9 5b 97 1b ac ..[...
[ 858.126522] sungem: sungem wrong csum : 0836/19e9, len 90 bytes, c0000001fa185382
[ 858.126530] raw data: 00000000: 00 0d 93 43 81 62 d4 3d 7e 4c 48 b7 86 dd 61 01 ...C.b.=~LH...a.
[ 858.126532] raw data: 00000010: 1e b1 00 20 06 40 20 01 0a 62 17 11 88 01 00 00 ... .@ ..b......
[ 858.126535] raw data: 00000020: 00 00 00 00 0a 38 20 01 0a 62 17 11 88 01 00 00 .....8 ..b......
[ 858.126537] raw data: 00000030: 00 00 00 00 00 07 94 b4 00 16 86 f5 2a 04 36 cb ............*.6.
[ 858.126540] raw data: 00000040: 50 65 80 10 05 93 3e 56 00 00 01 01 08 0a 58 b2 Pe....>V......X.
[ 858.126542] raw data: 00000050: de 56 61 5f 30 4d 1d 58 42 d2 .Va_0M.XB.
[ 858.131559] sungem: sungem wrong csum : 5891/c98d, len 90 bytes, c0000001fa185102
[ 858.131567] raw data: 00000000: 00 0d 93 43 81 62 d4 3d 7e 4c 48 b7 86 dd 61 01 ...C.b.=~LH...a.
[ 858.131570] raw data: 00000010: 1e b1 00 20 06 40 20 01 0a 62 17 11 88 01 00 00 ... .@ ..b......
[ 858.131572] raw data: 00000020: 00 00 00 00 0a 38 20 01 0a 62 17 11 88 01 00 00 .....8 ..b......
[ 858.131574] raw data: 00000030: 00 00 00 00 00 07 94 b4 00 16 86 f5 2a 04 36 cb ............*.6.
[ 858.131577] raw data: 00000040: 50 a1 80 10 05 93 3e 10 00 00 01 01 08 0a 58 b2 P.....>.......X.
[ 858.131579] raw data: 00000050: de 5b 61 5f 30 52 3f ea 70 9b .[a_0R?.p.
Andreas.
--
Andreas Schwab, schwab@xxxxxxxxxxxxxx
GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1
"And now for something completely different."