On 15/02/2026 15:51, Andrey Skvortsov wrote: > total_size is sum of record->size and record->ecc_notice_size (ECC: No > errors detected). When ECC is not used, then there is no problem. > When ECC is enabled, then ftrace dump is decoded incorrectly after > restart. > > First this affects starting offset calculation, that breaks > reading of all ftrace records. > > CPU:66 ts:51646260179894273 3818ffff80008002 fe00ffff800080f0 > 0x3818ffff80008002 <- 0xfe00ffff800080f0 > CPU:66 ts:56589664458375169 3818ffff80008002 ff02ffff800080f0 > 0x3818ffff80008002 <- 0xff02ffff800080f0 > CPU:67 ts:13194139533313 afe4ffff80008002 1ffff800080f0 > 0xafe4ffff80008002 <- 0x1ffff800080f0 > CPU:67 ts:13194139533313 b7d0ffff80008001 100ffff80008002 > 0xb7d0ffff80008001 <- 0x100ffff80008002 > CPU:67 ts:51646260179894273 8de0ffff80008001 202ffff80008002 > 0x8de0ffff80008001 <- 0x202ffff80008002 > > Second ECC notice message is printed like ftrace record and as a > result couple of last records are completely wrong. > > For example, when the starting offset is fixed: > > CPU:0 ts:113 ffffffc00879bd04 ffffffc0080dc08c cpuidle_enter <- > do_idle+0x20c/0x290 > CPU:0 ts:114 ffffffc00879bd04 ffffffc0080dc08c cpuidle_enter <- > do_idle+0x20c/0x290 > CPU:100 ts:28259048229270629 6f4e203a4343450a 2073726f72726520 > 0x6f4e203a4343450a <- 0x2073726f72726520 > > Signed-off-by: Andrey Skvortsov <[email protected]>
Thanks for noticing that! I've managed to reproduce it here and your patch indeed fixes the issue - I've tested on 6.19 with ramoops. Feel free to add my: Tested-by: Guilherme G. Piccoli <[email protected]> Cheers, Guilherme
