On Mon, Apr 3, 2023 at 12:29 PM Lucas Tanure <tanure@xxxxxxxxx> wrote: > > On Sun, Apr 2, 2023 at 1:55 PM Bagas Sanjaya <bagasdotme@xxxxxxxxx> wrote: > > > > On Sun, Apr 02, 2023 at 09:10:36AM +0100, Lucas Tanure wrote: > > > Log: > > > > > > [ 9.792966] SError Interrupt on CPU3, code 0x00000000bf000000 -- SError > > > [ 9.792980] CPU: 3 PID: 3471 Comm: kded5 Tainted: G C 6.2.0 #1 > > > [ 9.792985] Hardware name: Khadas VIM3 (DT) > > > [ 9.792987] pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) > > > [ 9.792991] pc : kmem_cache_free_bulk.part.98+0x1f0/0x528 > > > [ 9.793004] lr : kmem_cache_free_bulk.part.98+0x2f8/0x528 > > > [ 9.793008] sp : ffff80000a2eb7f0 > > > [ 9.793009] x29: ffff80000a2eb7f0 x28: ffff00001f358518 x27: ffff000000008800 > > > [ 9.793016] x26: ffff00000262b300 x25: ffff00000262b300 x24: 0000000000000001 > > > [ 9.793019] x23: ffff00000262b000 x22: 0000000000000000 x21: ffff00001f358538 > > > [ 9.793022] x20: fffffc0000098ac0 x19: 0000000000000004 x18: 0000000000000040 > > > [ 9.793025] x17: 0000000000000018 x16: 00000000000007f8 x15: 0000000000000003 > > > [ 9.793028] x14: 0000000000000006 x13: ffff800008e48550 x12: 0000ffff9dc91fff > > > [ 9.793031] x11: 0000000000000004 x10: 0000000000000001 x9 : ffff000007e93680 > > > [ 9.793035] x8 : 0000000000000020 x7 : ffff000001d2b100 x6 : 0000000000000007 > > > [ 9.793037] x5 : 0000000000000020 x4 : ffff000000008800 x3 : 0000000000000001 > > > [ 9.793040] x2 : 0000000000000007 x1 : 0000000000000000 x0 : ffff00001f358540 > > > [ 9.793045] Kernel panic - not syncing: Asynchronous SError Interrupt > > > > > > This doesn't happen with downstream Khadas 6.2 kernel, and that's > > > because the downstream kernel removed this from > > > early_init_dt_reserve_memory (drivers/of/fdt.c): > > > > > > /* > > > * If the memory is already reserved (by another region), we > > > * should not allow it to be marked nomap, but don't worry > > > * if the region isn't memory as it won't be mapped. > > > */ > > > if (memblock_overlaps_region(&memblock.memory, base, size) && > > > memblock_is_region_reserved(base, size)) > > > return -EBUSY; > > > > > > > What commit on downstream kernel that fix the issue? > Here: > https://github.com/khadas/linux/commit/2cb57b1071bf69f615fedc999b7ecacf2cde7228 > > Can you reproduce > > on mainline with above conditional removed? > No, without that code mainline works fine. > > > Alternatively, can > > you post the downstream fix here? > Same https://github.com/khadas/linux/commit/2cb57b1071bf69f615fedc999b7ecacf2cde7228 > > > > > Also, can you find last working commit on mainline? If so, this is > > regression. > That is difficult as 5.13.0 has the line: > OF: fdt: Reserved memory: failed to reserve memory for node > 'secmon@5000000': base 0x0000000005000000, size 3 MiB > But doesn't crash. It could be that no process used that address so no crash. > > > > > Thanks. > > > > -- > > An old man doll... just what I always wanted! - Clara Hi, I git bisect point it out commit that even reverting it would trigger the panic. So this is a memory corruption problem that a simple git bisect will not find the correct offending commit. I managed to understand a little more about the issue: 1 ) early_init_fdt_scan_reserved_mem is executed first, reserves [0x0000000005000000-0x00000000052fffff] but doesn't mark as no-map. 2 ) early_init_dt_reserve_memory tries to mark that region as nomap, but it is already reserved and memblock_overlaps_region and memblock_is_region_reserved return true, so it fails to mark as nomap. 3 ) kernel uses that memory and crashes I think we have two options here: 1) Allow early_init_dt_reserve_memory mark nomap memory that is already reserved 2) Make early_init_fdt_scan_reserved_mem reserve with the flag nomap if necessary. I don't know if that's possible. Question MM guys, Mike Rapoport and Andrew Morton: - Is it possible to make early_init_fdt_scan_reserved_mem reserve memory with flags? - It ok for early_init_fdt_scan_reserved_mem to mark regions already reserved as nomap? Thanks Lucas
