On 13. 01. 2023. 14:40, Mirsad Goran Todorovac wrote: > On 13.1.2023. 11:14, 黄朝阳 (Zhaoyang Huang) wrote: >>> On 13.1.2023. 7:20, 黄朝阳 (Zhaoyang Huang) wrote: >>>>> /sys/kernel/debug/kmemleak output: backtrace not printed since >>>>> 6.2.0-rc1 >>>>> >>>>> >>>>>> On 12. 01. 2023. 20:50, Mirsad Todorovac wrote: >>>>>>> Hi all, >>>>>>> >>>>>>> there seems to be a problem with the output of >>>>>> /sys/kernel/debug/kmemleak: >>>>>>> >>>>>>> [root@pc-mtodorov ~]# cat /sys/kernel/debug/kmemleak unreferenced >>>>>>> object 0xffff951c118568b0 (size 16): >>>>>>> comm "kworker/u12:2", pid 56, jiffies 4294893952 (age 4356.548s) >>>>>>> hex dump (first 16 bytes): >>>>>>> 6d 65 6d 73 74 69 63 6b 30 00 00 00 00 00 00 00 memstick0....... >>>>>>> backtrace: >>>>>>> [root@pc-mtodorov ~]# >>>>>>> >>>>>>> Apparently, backtrace of called functions on the stack is no longer >>>>>>> printed >>>>>> with the list of memory leaks. >>>>>>> >>>>>>> This appeared on Lenovo desktop 10TX000VCR, with AlmaLinux 8.7 and >>>>>>> BIOS version M22KT49A (11/10/2022) and 6.2-rc1 and 6.2-rc2 builds. >>>>>>> >>>>>>> This worked on 6.1 with the same CONFIG_KMEMLEAK=y and MGLRU >>>>>> enabled >>>>>>> on a vanilla mainstream kernel from Mr. Torvalds' tree. I don't >>>>>>> know if this is >>>>>> deliberate feature for some reason or a bug. >>>>>>> >>>>>>> Please find attached the config, lshw and kmemleak output. >>>>>>> >>>>>>> The bisection gave this commit as the culprit for the severed stack >>>>>>> backtrace print in /sys/kernel/debug/kmemleak: >>>>>>> >>>>>>> mtodorov@domac:~/linux/kernel/linux_torvalds$ git bisect good >>>>>>> 56a61617dd2276cbc56a6c868599716386d70041 is the first bad commit >>>>>>> commit 56a61617dd2276cbc56a6c868599716386d70041 >>>>>>> Author: Zhaoyang Huang <zhaoyang.huang@xxxxxxxxxx> >>>>>>> Date: Thu Oct 27 17:50:24 2022 +0800 >>>>>>> >>>>>>> mm: use stack_depot for recording kmemleak's backtrace >>>>>>> >>>>>>> Using stack_depot to record kmemleak's backtrace which has >>> been >>>>>>> implemented on slub for reducing redundant information. >>>>>>> >>>>>>> The complete bisect log is: >>>>>>> >>>>>>> mtodorov@domac:~/linux/kernel/linux_torvalds$ git bisect log git >>>>>>> bisect start '--' 'mm' >>>>>>> # good: [830b3c68c1fb1e9176028d02ef86f3cf76aa2476] Linux 6.1 git >>>>>>> bisect good 830b3c68c1fb1e9176028d02ef86f3cf76aa2476 >>>>>>> # bad: [1b929c02afd37871d5afb9d498426f83432e71c2] Linux 6.2-rc1 git >>>>>>> bisect bad 1b929c02afd37871d5afb9d498426f83432e71c2 >>>>>>> # good: [8b9ed79c2d587bec5f603d66801478a5af9af842] Merge tag >>>>>>> 'x86_asm_for_v6.2' of >>>>>>> git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip >>>>>>> git bisect good 8b9ed79c2d587bec5f603d66801478a5af9af842 >>>>>>> # good: [e83b39d6bbdb6d25bd6f5c258832774635d29b47] mm: make >>>>>>> drop_caches keep reclaiming on all nodes git bisect good >>>>>>> e83b39d6bbdb6d25bd6f5c258832774635d29b47 >>>>>>> # good: [9997bc017549acd6425e32300eff28424ffeeb6b] zsmalloc: >>>>>> implement >>>>>>> writeback mechanism for zsmalloc git bisect good >>>>>>> 9997bc017549acd6425e32300eff28424ffeeb6b >>>>>>> # good: [6287b7dae80944bfa37784a8f9d6861a4facaa6e] mm,thp,rmap: >>> fix >>>>>>> races between updates of subpages_mapcount git bisect good >>>>>>> 6287b7dae80944bfa37784a8f9d6861a4facaa6e >>>>>>> # good: [8fa590bf344816c925810331eea8387627bbeb40] Merge tag >>>>>>> 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm >>>>>>> git bisect good 8fa590bf344816c925810331eea8387627bbeb40 >>>>>>> # good: [4f292c4de4f6fb83776c0ff22674121eb6ddfa2f] Merge tag >>>>>>> 'x86_mm_for_6.2_v2' of >>>>>>> git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip >>>>>>> git bisect good 4f292c4de4f6fb83776c0ff22674121eb6ddfa2f >>>>>>> # bad: [1ea9d333ba475041efe43d9d9bc32e64aea2ea2b] Merge tag >>>>>>> 'mm-stable-2022-12-17-2' of >>>>>>> git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm >>>>>>> git bisect bad 1ea9d333ba475041efe43d9d9bc32e64aea2ea2b >>>>>>> # bad: [56a61617dd2276cbc56a6c868599716386d70041] mm: use >>>>>> stack_depot >>>>>>> for recording kmemleak's backtrace git bisect bad >>>>>>> 56a61617dd2276cbc56a6c868599716386d70041 >>>>>>> # good: [61b963b52f59524e27692bc1c14bfb2459e32eb3] mm/gup_test: >>>>>> free >>>>>>> memory allocated via kvcalloc() using kvfree() git bisect good >>>>>>> 61b963b52f59524e27692bc1c14bfb2459e32eb3 >>>>>>> # first bad commit: [56a61617dd2276cbc56a6c868599716386d70041] >>> mm: >>>>>> use >>>>>>> stack_depot for recording kmemleak's backtrace # good: >>>>>>> [9102b78b6f6ae6af3557114c265c266b312c1319] maple_tree: update >>>>>>> copyright dates for test code git bisect good >>>>>>> 9102b78b6f6ae6af3557114c265c266b312c1319 >>>>>>> # first bad commit: [56a61617dd2276cbc56a6c868599716386d70041] >>> mm: >>>>>> use >>>>>>> stack_depot for recording kmemleak's backtrace You have mail in >>>>>>> /var/mail/mtodorov mtodorov@domac:~/linux/kernel/linux_torvalds$ >>>>>>> >>>>>>> The platform is 10TX000VCR >>>>>> (LENOVO_MT_10TX_BU_Lenovo_FM_V530S-07ICB) >>>>>>> running AlmaLinux 8.7 (CentOS clone) and BIOS M22KT49A. >>>>>>> >>>>>>> GCC used was: >>>>>>> >>>>>>> mtodorov@domac:~/linux/kernel/linux_torvalds$ gcc --version gcc >>>>>>> (Debian 8.3.0-6) 8.3.0 Copyright (C) 2018 Free Software Foundation, >>>>>>> Inc. >>>>>>> This is free software; see the source for copying conditions. >>>>>>> There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A >>>>>> PARTICULAR PURPOSE. >>>>>>> mtodorov@domac:~/linux/kernel/linux_torvalds$ >>>>>>> >>>>>>> Hope this helps. >>>>>>> >>>>>>> I lack the insight to pinpoint the exact fault in the patch. >>>>>> >>>>>> P.S. >>>>>> >>>>>> To further complicate things, on Ubuntu 22.10 Lenovo Ideapad 3 >>>>>> 15ITL6 laptop the kmemleak stack backtrace is printed correctly with >>>>>> the same kernels (but .deb instead of .rpm for the same build): >>>>>> >>>>>> unreferenced object 0xffff94ca88e042d0 (size 80): >>>>>> comm "thermald", pid 768, jiffies 4294893592 (age 78581.504s) >>>>>> hex dump (first 32 bytes): >>>>>> 00 00 00 00 00 00 00 00 0d 01 2d 00 00 00 00 00 ..........-..... >>>>>> af 07 01 80 fd ac ff ff 00 00 00 00 00 00 00 00 ................ >>>>>> backtrace: >>>>>> [<ffffffffa0dcb921>] slab_post_alloc_hook+0x91/0x320 >>>>>> [<ffffffffa0dcfb79>] kmem_cache_alloc+0x169/0x2f0 >>>>>> [<ffffffffa12b1def>] acpi_os_acquire_object+0x2c/0x32 >>>>>> [<ffffffffa12b1ea2>] acpi_ps_alloc_op+0x4a/0x99 >>>>>> [<ffffffffa12af5c8>] acpi_ps_get_next_arg+0x611/0x761 >>>>>> [<ffffffffa12afbbc>] acpi_ps_parse_loop+0x494/0x8d7 >>>>>> [<ffffffffa12b1434>] acpi_ps_parse_aml+0x1bb/0x561 >>>>>> [<ffffffffa12b24c8>] acpi_ps_execute_method+0x20f/0x2d5 >>>>>> [<ffffffffa12a7acf>] acpi_ns_evaluate+0x34d/0x4f3 >>>>>> [<ffffffffa12ad6a3>] acpi_evaluate_object+0x180/0x3ae >>>>>> [<ffffffffa1269ca8>] acpi_run_osc+0x128/0x250 >>>>>> [<ffffffffc0bbb14f>] int3400_thermal_run_osc+0x6f/0xc0 >>>>>> [int3400_thermal] >>>>>> [<ffffffffc0bbb293>] current_uuid_store+0xe3/0x120 >>> [int3400_thermal] >>>>>> [<ffffffffa13b8ed4>] dev_attr_store+0x14/0x30 >>>>>> [<ffffffffa0ee0458>] sysfs_kf_write+0x38/0x50 >>>>>> [<ffffffffa0edf516>] kernfs_fop_write_iter+0x146/0x1d0 You have >>>>>> new mail in /var/mail/root >>>>>> root@marvin-IdeaPad-3-15ITL6:/home/marvin# >>>>>> >>>>>> Regards, >>>>>> Mirsad >>>>> >>>>> thanks for head up. Could you please help to check If >>>>> CONFIG_STACKTRACE and CONFIG_STACKDEPOT is enabled on the fault >>> kernel? >>>> Please try the patch below if the configs are right. I think it should >>>> be caused by the late ready for kmemleak >>>> >>>> commit 556eb1927da99ab366e370d593fc32da946768c3 >>>> Author: Zhaoyang Huang <zhaoyang.huang@xxxxxxxxxx> >>>> Date: Fri Jan 13 14:13:39 2023 +0800 >>>> >>>> mm: instroduce a flag to indicate stack_depot's ready >>>> >>>> try to solve the kmemleak's late ready issue. >>>> >>>> diff --git a/mm/kmemleak.c b/mm/kmemleak.c index 762b91f..7eb24bc >>>> 100644 >>>> --- a/mm/kmemleak.c >>>> +++ b/mm/kmemleak.c >>>> @@ -216,6 +216,7 @@ struct kmemleak_object { static int >>> kmemleak_warning; >>>> /* set if a fatal kmemleak error has occurred */ static int >>>> kmemleak_error; >>>> +static int kmemleak_stadep_initialized; >>>> >>>> /* minimum and maximum address that may be valid pointers */ static >>> unsigned long min_addr = ULONG_MAX; @@ -601,7 +602,7 @@ static noinline >>> depot_stack_handle_t set_track_prepare(void) >>>> unsigned long entries[MAX_TRACE]; >>>> unsigned int nr_entries; >>>> >>>> - if (!kmemleak_initialized) >>>> + if (!kmemleak_stadep_initialized) >>>> return 0; >>>> nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 3); >>>> trace_handle = stack_depot_save(entries, nr_entries, >>> GFP_NOWAIT); @@ -2110,6 +2111,7 @@ void __init kmemleak_init(void) >>>> create_object((unsigned long)__start_ro_after_init, >>>> __end_ro_after_init - >>> __start_ro_after_init, >>>> KMEMLEAK_GREY, GFP_ATOMIC); >>>> + kmemleak_stadep_initialized = 1; >>>> } >>> >>> Hi, Zhaoyang, >>> >>> Sorry, applied the patch and rebuilt, but it didn't work for me: >>> >>> [root@pc-mtodorov marvin]# uname -rms >>> Linux 6.2.0-rc3-mglru-kmemlk-patch-zhaoyang1+ x86_64 [root@pc-mtodorov >>> marvin]# cat /sys/kernel/debug/kmemleak [root@pc-mtodorov marvin]# echo >>> scan | tee !$ echo scan | tee /sys/kernel/debug/kmemleak scan >>> [root@pc-mtodorov marvin]# cat /sys/kernel/debug/kmemleak unreferenced >>> object 0xffff98938fed1ee0 (size 16): >>> comm "kworker/u12:2", pid 57, jiffies 4294894053 (age 66.616s) >>> hex dump (first 16 bytes): >>> 6d 65 6d 73 74 69 63 6b 30 00 00 00 00 00 00 00 memstick0....... >>> backtrace: >>> [root@pc-mtodorov marvin]# >>> >>> Still the stack backtrace list is severed. >>> CONFIG_STACKDEPOT and CONFIG_STACKTRACE are both "=y": >>> >>> [root@pc-mtodorov marvin]# grep -E 'CONFIG_(STACKTRACE|STACKDEPOT)' >>> /boot/config-6.2.0-rc3-mglru-kmemlk-patch-zhaoyang1+ >>> CONFIG_STACKTRACE_SUPPORT=y >>> CONFIG_STACKDEPOT=y >>> # CONFIG_STACKTRACE_BUILD_ID is not set >>> CONFIG_STACKTRACE=y >>> [root@pc-mtodorov marvin]# >>> >>> Your patch was successfully applied (after some tweaks): >>> >>> mtodorov@domac:~/linux/kernel/linux_torvalds$ git diff mm diff --git >>> a/mm/kmemleak.c b/mm/kmemleak.c index 92f670edbf51..78fd3b89b057 >>> 100644 >>> --- a/mm/kmemleak.c >>> +++ b/mm/kmemleak.c >>> @@ -216,6 +216,7 @@ static int kmemleak_initialized; >>> static int kmemleak_warning; >>> /* set if a fatal kmemleak error has occurred */ >>> static int kmemleak_error; >>> +static int kmemleak_stadep_initialized; >>> >>> /* minimum and maximum address that may be valid pointers */ >>> static unsigned long min_addr = ULONG_MAX; @@ -601,7 +602,7 @@ static >>> noinline depot_stack_handle_t set_track_prepare(void) >>> unsigned long entries[MAX_TRACE]; >>> unsigned int nr_entries; >>> >>> - if (!kmemleak_initialized) >>> + if (!kmemleak_stadep_initialized) >>> return 0; >>> nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 3); >>> trace_handle = stack_depot_save(entries, nr_entries, >>> GFP_NOWAIT); @@ -2110,6 +2111,7 @@ void __init kmemleak_init(void) >>> create_object((unsigned long)__start_ro_after_init, >>> __end_ro_after_init - >>> __start_ro_after_init, >>> KMEMLEAK_GREY, GFP_ATOMIC); >>> + kmemleak_stadep_initialized = 1; >>> } >>> >>> /* >>> mtodorov@domac:~/linux/kernel/linux_torvalds$ >>> >>> Please verify that the above is correct. >> It is correct. Another reason could be the stack is less than 3 layers which could be surpassed by stack_trace_save. Could you please try to modify the code as bellow and try again. >> static noinline depot_stack_handle_t set_track_prepare(void) >> { >> depot_stack_handle_t trace_handle; >> unsigned long entries[MAX_TRACE]; >> unsigned int nr_entries; >> >> if (!kmemleak_initialized) >> return 0; >> - nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 3); >> + nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 0); >> trace_handle = stack_depot_save(entries, nr_entries, GFP_NOWAIT); >> >> return trace_handle; >> } > > Tried that, rebuilt, still no luck: > > [root@pc-mtodorov marvin]# uname -rms > Linux 6.2.0-rc3-mglru-kmemlk-patch-zhaoyang2+ x86_64 > [root@pc-mtodorov marvin]# cat /sys/kernel/debug/kmemleak > unreferenced object 0xffff8e8c86483c00 (size 16): > comm "kworker/u12:5", pid 364, jiffies 4294894029 (age 135.024s) > hex dump (first 16 bytes): > 6d 65 6d 73 74 69 63 6b 30 00 00 00 00 00 00 00 memstick0....... > backtrace: > unreferenced object 0xffff8e8c8edb3f70 (size 16): > comm "kworker/u12:5", pid 364, jiffies 4294894033 (age 135.008s) > hex dump (first 16 bytes): > 6d 65 6d 73 74 69 63 6b 30 00 00 00 00 00 00 00 memstick0....... > backtrace: > [root@pc-mtodorov marvin]# > > What I have here is: > > static noinline depot_stack_handle_t set_track_prepare(void) > { > depot_stack_handle_t trace_handle; > unsigned long entries[MAX_TRACE]; > unsigned int nr_entries; > > if (!kmemleak_stadep_initialized) > return 0; > nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 0); > trace_handle = stack_depot_save(entries, nr_entries, GFP_NOWAIT); > > return trace_handle; > } > > Maybe this will help (dmesg says that Stack Depot is disabled due to errors?): > > [ 0.072031] Memory: 16152080K/16658536K available (18432K kernel code, 4118K rwdata, 7184K rodata, 4420K init, 7684K bss, 506196K reserved, 0K cma-reserved) > [ 0.072219] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=6, Nodes=1 > [ 0.072222] Stack Depot allocating hash table of 1048576 entries with kvcalloc > [ 0.072226] swapper: vmalloc error: size 8388608, vm_struct allocation failed, mode:0xdc0(GFP_KERNEL|__GFP_ZERO), nodemask=(null),cpuset=(null),mems_allowed=0-1023 > [ 0.072235] CPU: 0 PID: 0 Comm: swapper Not tainted 6.2.0-rc3-mglru-kmemlk-patch-zhaoyang2+ #23 > [ 0.072237] Hardware name: LENOVO 10TX000VCR/3140, BIOS M22KT49A 11/10/2022 > [ 0.072238] Call Trace: > [ 0.072240] <TASK> > [ 0.072242] dump_stack_lvl+0x49/0x63 > [ 0.072248] dump_stack+0x10/0x16 > [ 0.072250] warn_alloc.cold.161+0x75/0xe8 > [ 0.072255] ? __get_vm_area_node+0x14d/0x160 > [ 0.072260] __vmalloc_node_range+0x5e5/0x7d0 > [ 0.072264] ? stack_depot_init.cold.2+0x7e/0xb3 > [ 0.072267] ? __kmalloc_large_node+0xf8/0x150 > [ 0.072270] ? kvmalloc_node+0x4f/0xe0 > [ 0.072274] kvmalloc_node+0xb1/0xe0 > [ 0.072276] ? stack_depot_init.cold.2+0x7e/0xb3 > [ 0.072278] stack_depot_init.cold.2+0x7e/0xb3 > [ 0.072280] kmemleak_init+0x1b/0x114 > [ 0.072284] start_kernel+0x710/0x9dc > [ 0.072288] x86_64_start_reservations+0x24/0x2a > [ 0.072290] x86_64_start_kernel+0xf2/0xfd > [ 0.072292] secondary_startup_64_no_verify+0xe5/0xeb > [ 0.072297] </TASK> > [ 0.072298] Mem-Info: > [ 0.072299] active_anon:0 inactive_anon:0 isolated_anon:0 > active_file:0 inactive_file:0 isolated_file:0 > unevictable:0 dirty:0 writeback:0 > slab_reclaimable:0 slab_unreclaimable:26 > mapped:0 shmem:0 pagetables:0 > sec_pagetables:0 bounce:0 > kernel_misc_reclaimable:0 > free:4037994 free_pcp:0 free_cma:0 > [ 0.072303] Node 0 active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB isolated(anon):0kB isolated(file):0kB mapped:0kB dirty:0kB writeback:0kB shmem:0kB shmem_thp: 0kB shmem_pmdmapped: 0kB anon_thp: 0kB writeback_tmp:0kB kernel_stack:0kB pagetables:0kB sec_pagetables:0kB all_unreclaimable? no > [ 0.072307] Node 0 DMA free:14336kB boost:0kB min:0kB low:0kB high:0kB reserved_highatomic:0KB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB writepending:0kB present:15992kB managed:14336kB mlocked:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB > [ 0.072311] lowmem_reserve[]: 0 0 0 0 0 > [ 0.072314] Node 0 DMA32 free:2085160kB boost:0kB min:0kB low:0kB high:0kB reserved_highatomic:0KB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB writepending:0kB present:2257392kB managed:2085160kB mlocked:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB > [ 0.072318] lowmem_reserve[]: 0 0 0 0 0 > [ 0.072321] Node 0 Normal free:14052480kB boost:0kB min:0kB low:0kB high:0kB reserved_highatomic:0KB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB writepending:0kB present:14385152kB managed:14052844kB mlocked:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB > [ 0.072325] lowmem_reserve[]: 0 0 0 0 0 > [ 0.072328] Node 0 DMA: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 2*1024kB (UM) 2*2048kB (M) 2*4096kB (M) = 14336kB > [ 0.072338] Node 0 DMA32: 8*4kB (M) 9*8kB (M) 8*16kB (M) 8*32kB (M) 7*64kB (M) 7*128kB (M) 8*256kB (M) 7*512kB (M) 5*1024kB (M) 6*2048kB (M) 503*4096kB (M) = 2085160kB > [ 0.072352] Node 0 Normal: 8*4kB (UM) 8*8kB (M) 2*16kB (UM) 2*32kB (M) 1*64kB (M) 3*128kB (UM) 2*256kB (M) 4*512kB (UM) 2*1024kB (UM) 3*2048kB (UM) 3428*4096kB (M) = 14052480kB > [ 0.072366] 0 total pagecache pages > [ 0.072367] 0 pages in swap cache > [ 0.072367] Free swap = 0kB > [ 0.072368] Total swap = 0kB > [ 0.072369] 4164634 pages RAM > [ 0.072369] 0 pages HighMem/MovableOnly > [ 0.072370] 126549 pages reserved > [ 0.072371] 0 pages hwpoisoned > [ 0.072372] Stack Depot hash table allocation failed, disabling Hi again, I have an additional info: Here we see Stack Depot trying to alocate 1024 * 1024 entires on a 16 GiB RAM AlmaLinux 8.7 (CentOS clone): [ 0.071875] Stack Depot allocating hash table of 1048576 entries with kvcalloc [ 0.071879] swapper: vmalloc error: size 8388608, vm_struct allocation failed, mode:0xdc0(GFP_KERNEL|__GFP_ZERO), nodemask=(null),cpuset=(null),mems_allowed=0-1023 [ 0.071888] CPU: 0 PID: 0 Comm: swapper Not tainted 6.2.0-rc3-mglru-kmemlk-nokasan-fixed-rcu+ #2 [ 0.071891] Hardware name: LENOVO 10TX000VCR/3140, BIOS M22KT49A 11/10/2022 On another machine with just 8 GiB this mechanism is less demanding, requests slightly more than 512 * 1024 entries and succeeds: [ 0.037858] Stack Depot allocating hash table of 524288 entries with kvcalloc [ 0.038225] ftrace: allocating 52222 entries in 204 pages I am not that deep into kernel code to debug this :-( As plain kvcalloc() fails, the only thing that comes to mind - maybe 0.072 s since boot is still too early to request 8.3 MB? What are the probable causes that kvcalloc and vmalloc should fail? Thanks, Mirsad -- Mirsad Goran Todorovac Sistem inženjer Grafički fakultet | Akademija likovnih umjetnosti Sveučilište u Zagrebu System engineer Faculty of Graphic Arts | Academy of Fine Arts University of Zagreb, Republic of Croatia The European Union