* [PATCH] slub/slub_kunit:fix a panic due to __kmalloc_cache_noprof incorretly use
@ 2024-10-21 6:59 xiaopeitux
2024-10-21 17:42 ` Suren Baghdasaryan
0 siblings, 1 reply; 8+ messages in thread
From: xiaopeitux @ 2024-10-21 6:59 UTC (permalink / raw)
To: akpm, linux-kernel, linux-mm, surenb, yuzhao; +Cc: xiaopei01, gehao, xiongxin
From: Pei Xiao <xiaopei01@kylinos.cn>
'modprobe slub_kunit',will have a panic.The root cause is that
__kmalloc_cache_noprof was directly ,which resulted in no alloc_tag
being allocated.This caused current->alloc_tag to be null,leading to
a null pointer dereference in alloc_tag_ref_set.
Here is the log for the panic:
[ 74.779373][ T2158] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
[ 74.780130][ T2158] Mem abort info:
[ 74.780406][ T2158] ESR = 0x0000000096000004
[ 74.780756][ T2158] EC = 0x25: DABT (current EL), IL = 32 bits
[ 74.781225][ T2158] SET = 0, FnV = 0
[ 74.781529][ T2158] EA = 0, S1PTW = 0
[ 74.781836][ T2158] FSC = 0x04: level 0 translation fault
[ 74.782288][ T2158] Data abort info:
[ 74.782577][ T2158] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
[ 74.783068][ T2158] CM = 0, WnR = 0, TnD = 0, TagAccess = 0
[ 74.783533][ T2158] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[ 74.784010][ T2158] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000105f34000
[ 74.784586][ T2158] [0000000000000020] pgd=0000000000000000, p4d=0000000000000000
[ 74.785293][ T2158] Internal error: Oops: 0000000096000004 [#1] SMP
[ 74.785805][ T2158] Modules linked in: slub_kunit kunit ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute ip6table_nat ip6table_mangle 4
[ 74.790661][ T2158] CPU: 0 UID: 0 PID: 2158 Comm: kunit_try_catch Kdump: loaded Tainted: G W N 6.12.0-rc3+ #2
[ 74.791535][ T2158] Tainted: [W]=WARN, [N]=TEST
[ 74.791889][ T2158] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
[ 74.792479][ T2158] pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 74.793101][ T2158] pc : alloc_tagging_slab_alloc_hook+0x120/0x270
[ 74.793607][ T2158] lr : alloc_tagging_slab_alloc_hook+0x120/0x270
[ 74.794095][ T2158] sp : ffff800084d33cd0
[ 74.794418][ T2158] x29: ffff800084d33cd0 x28: 0000000000000000 x27: 0000000000000000
[ 74.795095][ T2158] x26: 0000000000000000 x25: 0000000000000012 x24: ffff80007b30e314
[ 74.795822][ T2158] x23: ffff000390ff6f10 x22: 0000000000000000 x21: 0000000000000088
[ 74.796555][ T2158] x20: ffff000390285840 x19: fffffd7fc3ef7830 x18: ffffffffffffffff
[ 74.797283][ T2158] x17: ffff8000800e63b4 x16: ffff80007b33afc4 x15: ffff800081654c00
[ 74.798011][ T2158] x14: 0000000000000000 x13: 205d383531325420 x12: 5b5d383734363537
[ 74.798744][ T2158] x11: ffff800084d337e0 x10: 000000000000005d x9 : 00000000ffffffd0
[ 74.799476][ T2158] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008219d188 x6 : c0000000ffff7fff
[ 74.800206][ T2158] x5 : ffff0003fdbc9208 x4 : ffff800081edd188 x3 : 0000000000000001
[ 74.800932][ T2158] x2 : 0beaa6dee1ac5a00 x1 : 0beaa6dee1ac5a00 x0 : ffff80037c2cb000
[ 74.801656][ T2158] Call trace:
[ 74.801954][ T2158] alloc_tagging_slab_alloc_hook+0x120/0x270
[ 74.802494][ T2158] __kmalloc_cache_noprof+0x148/0x33c
[ 74.802976][ T2158] test_kmalloc_redzone_access+0x4c/0x104 [slub_kunit]
[ 74.803607][ T2158] kunit_try_run_case+0x70/0x17c [kunit]
[ 74.804124][ T2158] kunit_generic_run_threadfn_adapter+0x2c/0x4c [kunit]
[ 74.804768][ T2158] kthread+0x10c/0x118
[ 74.805141][ T2158] ret_from_fork+0x10/0x20
[ 74.805540][ T2158] Code: b9400a80 11000400 b9000a80 97ffd858 (f94012d3)
[ 74.806176][ T2158] SMP: stopping secondary CPUs
[ 74.808130][ T2158] Starting crashdump kernel...
Signed-off-by: Pei Xiao <xiaopei01@kylinos.cn>
---
include/linux/slab.h | 1 +
lib/slub_kunit.c | 2 +-
2 files changed, 2 insertions(+), 1 deletion(-)
diff --git a/include/linux/slab.h b/include/linux/slab.h
index 10a971c2bde3..0149d36cd311 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -827,6 +827,7 @@ void *__kmalloc_cache_noprof(struct kmem_cache *s, gfp_t flags, size_t size)
void *__kmalloc_cache_node_noprof(struct kmem_cache *s, gfp_t gfpflags,
int node, size_t size)
__assume_kmalloc_alignment __alloc_size(4);
+#define kmalloc_cache(...) alloc_hooks(__kmalloc_cache_noprof(__VA_ARGS__))
void *__kmalloc_large_noprof(size_t size, gfp_t flags)
__assume_page_alignment __alloc_size(1);
diff --git a/lib/slub_kunit.c b/lib/slub_kunit.c
index 80e39f003344..4bf38f52dbbd 100644
--- a/lib/slub_kunit.c
+++ b/lib/slub_kunit.c
@@ -141,7 +141,7 @@ static void test_kmalloc_redzone_access(struct kunit *test)
{
struct kmem_cache *s = test_kmem_cache_create("TestSlub_RZ_kmalloc", 32,
SLAB_KMALLOC|SLAB_STORE_USER|SLAB_RED_ZONE);
- u8 *p = __kmalloc_cache_noprof(s, GFP_KERNEL, 18);
+ u8 *p = kmalloc_cache(s, GFP_KERNEL, 18);
kasan_disable_current();
--
2.34.1
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] slub/slub_kunit:fix a panic due to __kmalloc_cache_noprof incorretly use
2024-10-21 6:59 [PATCH] slub/slub_kunit:fix a panic due to __kmalloc_cache_noprof incorretly use xiaopeitux
@ 2024-10-21 17:42 ` Suren Baghdasaryan
2024-10-22 2:19 ` Hao Ge
0 siblings, 1 reply; 8+ messages in thread
From: Suren Baghdasaryan @ 2024-10-21 17:42 UTC (permalink / raw)
To: xiaopeitux
Cc: akpm, linux-kernel, linux-mm, yuzhao, xiaopei01, gehao, xiongxin,
Vlastimil Babka
On Sun, Oct 20, 2024 at 11:59 PM <xiaopeitux@foxmail.com> wrote:
>
> From: Pei Xiao <xiaopei01@kylinos.cn>
>
> 'modprobe slub_kunit',will have a panic.The root cause is that
> __kmalloc_cache_noprof was directly ,which resulted in no alloc_tag
> being allocated.This caused current->alloc_tag to be null,leading to
> a null pointer dereference in alloc_tag_ref_set.
I think the root cause of this crash is the bug that is fixed by
https://lore.kernel.org/all/20241020070819.307944-1-hao.ge@linux.dev/.
Do you get this crash if you apply that fix?
>
> Here is the log for the panic:
> [ 74.779373][ T2158] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
> [ 74.780130][ T2158] Mem abort info:
> [ 74.780406][ T2158] ESR = 0x0000000096000004
> [ 74.780756][ T2158] EC = 0x25: DABT (current EL), IL = 32 bits
> [ 74.781225][ T2158] SET = 0, FnV = 0
> [ 74.781529][ T2158] EA = 0, S1PTW = 0
> [ 74.781836][ T2158] FSC = 0x04: level 0 translation fault
> [ 74.782288][ T2158] Data abort info:
> [ 74.782577][ T2158] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
> [ 74.783068][ T2158] CM = 0, WnR = 0, TnD = 0, TagAccess = 0
> [ 74.783533][ T2158] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
> [ 74.784010][ T2158] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000105f34000
> [ 74.784586][ T2158] [0000000000000020] pgd=0000000000000000, p4d=0000000000000000
> [ 74.785293][ T2158] Internal error: Oops: 0000000096000004 [#1] SMP
> [ 74.785805][ T2158] Modules linked in: slub_kunit kunit ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute ip6table_nat ip6table_mangle 4
> [ 74.790661][ T2158] CPU: 0 UID: 0 PID: 2158 Comm: kunit_try_catch Kdump: loaded Tainted: G W N 6.12.0-rc3+ #2
> [ 74.791535][ T2158] Tainted: [W]=WARN, [N]=TEST
> [ 74.791889][ T2158] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
> [ 74.792479][ T2158] pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> [ 74.793101][ T2158] pc : alloc_tagging_slab_alloc_hook+0x120/0x270
> [ 74.793607][ T2158] lr : alloc_tagging_slab_alloc_hook+0x120/0x270
>
> [ 74.794095][ T2158] sp : ffff800084d33cd0
> [ 74.794418][ T2158] x29: ffff800084d33cd0 x28: 0000000000000000 x27: 0000000000000000
> [ 74.795095][ T2158] x26: 0000000000000000 x25: 0000000000000012 x24: ffff80007b30e314
> [ 74.795822][ T2158] x23: ffff000390ff6f10 x22: 0000000000000000 x21: 0000000000000088
> [ 74.796555][ T2158] x20: ffff000390285840 x19: fffffd7fc3ef7830 x18: ffffffffffffffff
> [ 74.797283][ T2158] x17: ffff8000800e63b4 x16: ffff80007b33afc4 x15: ffff800081654c00
> [ 74.798011][ T2158] x14: 0000000000000000 x13: 205d383531325420 x12: 5b5d383734363537
> [ 74.798744][ T2158] x11: ffff800084d337e0 x10: 000000000000005d x9 : 00000000ffffffd0
> [ 74.799476][ T2158] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008219d188 x6 : c0000000ffff7fff
> [ 74.800206][ T2158] x5 : ffff0003fdbc9208 x4 : ffff800081edd188 x3 : 0000000000000001
> [ 74.800932][ T2158] x2 : 0beaa6dee1ac5a00 x1 : 0beaa6dee1ac5a00 x0 : ffff80037c2cb000
> [ 74.801656][ T2158] Call trace:
> [ 74.801954][ T2158] alloc_tagging_slab_alloc_hook+0x120/0x270
> [ 74.802494][ T2158] __kmalloc_cache_noprof+0x148/0x33c
> [ 74.802976][ T2158] test_kmalloc_redzone_access+0x4c/0x104 [slub_kunit]
> [ 74.803607][ T2158] kunit_try_run_case+0x70/0x17c [kunit]
> [ 74.804124][ T2158] kunit_generic_run_threadfn_adapter+0x2c/0x4c [kunit]
> [ 74.804768][ T2158] kthread+0x10c/0x118
> [ 74.805141][ T2158] ret_from_fork+0x10/0x20
> [ 74.805540][ T2158] Code: b9400a80 11000400 b9000a80 97ffd858 (f94012d3)
> [ 74.806176][ T2158] SMP: stopping secondary CPUs
> [ 74.808130][ T2158] Starting crashdump kernel...
>
CC'ing Vlastimil.
This patch essentially reverts Vlastimil's "mm, slab: don't wrap
internal functions with alloc_hooks()" change. Please check why that
change was needed before proceeding.
If this change is indeed needed, please add:
Fixes: a0a44d9175b349 ("mm, slab: don't wrap internal functions with
alloc_hooks()")
> Signed-off-by: Pei Xiao <xiaopei01@kylinos.cn>
> ---
> include/linux/slab.h | 1 +
> lib/slub_kunit.c | 2 +-
> 2 files changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/include/linux/slab.h b/include/linux/slab.h
> index 10a971c2bde3..0149d36cd311 100644
> --- a/include/linux/slab.h
> +++ b/include/linux/slab.h
> @@ -827,6 +827,7 @@ void *__kmalloc_cache_noprof(struct kmem_cache *s, gfp_t flags, size_t size)
> void *__kmalloc_cache_node_noprof(struct kmem_cache *s, gfp_t gfpflags,
> int node, size_t size)
> __assume_kmalloc_alignment __alloc_size(4);
> +#define kmalloc_cache(...) alloc_hooks(__kmalloc_cache_noprof(__VA_ARGS__))
>
> void *__kmalloc_large_noprof(size_t size, gfp_t flags)
> __assume_page_alignment __alloc_size(1);
> diff --git a/lib/slub_kunit.c b/lib/slub_kunit.c
> index 80e39f003344..4bf38f52dbbd 100644
> --- a/lib/slub_kunit.c
> +++ b/lib/slub_kunit.c
> @@ -141,7 +141,7 @@ static void test_kmalloc_redzone_access(struct kunit *test)
> {
> struct kmem_cache *s = test_kmem_cache_create("TestSlub_RZ_kmalloc", 32,
> SLAB_KMALLOC|SLAB_STORE_USER|SLAB_RED_ZONE);
> - u8 *p = __kmalloc_cache_noprof(s, GFP_KERNEL, 18);
> + u8 *p = kmalloc_cache(s, GFP_KERNEL, 18);
>
> kasan_disable_current();
>
> --
> 2.34.1
>
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] slub/slub_kunit:fix a panic due to __kmalloc_cache_noprof incorretly use
2024-10-21 17:42 ` Suren Baghdasaryan
@ 2024-10-22 2:19 ` Hao Ge
2024-10-22 15:27 ` Vlastimil Babka
0 siblings, 1 reply; 8+ messages in thread
From: Hao Ge @ 2024-10-22 2:19 UTC (permalink / raw)
To: Suren Baghdasaryan, xiaopeitux
Cc: akpm, linux-kernel, linux-mm, yuzhao, xiaopei01, gehao, xiongxin,
Vlastimil Babka
On 10/22/24 01:42, Suren Baghdasaryan wrote:
> On Sun, Oct 20, 2024 at 11:59 PM <xiaopeitux@foxmail.com> wrote:
>> From: Pei Xiao <xiaopei01@kylinos.cn>
>>
>> 'modprobe slub_kunit',will have a panic.The root cause is that
>> __kmalloc_cache_noprof was directly ,which resulted in no alloc_tag
>> being allocated.This caused current->alloc_tag to be null,leading to
>> a null pointer dereference in alloc_tag_ref_set.
> I think the root cause of this crash is the bug that is fixed by
> https://lore.kernel.org/all/20241020070819.307944-1-hao.ge@linux.dev/.
> Do you get this crash if you apply that fix?
Yes, this patch has resolved the panic issue.
>> Here is the log for the panic:
>> [ 74.779373][ T2158] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
>> [ 74.780130][ T2158] Mem abort info:
>> [ 74.780406][ T2158] ESR = 0x0000000096000004
>> [ 74.780756][ T2158] EC = 0x25: DABT (current EL), IL = 32 bits
>> [ 74.781225][ T2158] SET = 0, FnV = 0
>> [ 74.781529][ T2158] EA = 0, S1PTW = 0
>> [ 74.781836][ T2158] FSC = 0x04: level 0 translation fault
>> [ 74.782288][ T2158] Data abort info:
>> [ 74.782577][ T2158] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
>> [ 74.783068][ T2158] CM = 0, WnR = 0, TnD = 0, TagAccess = 0
>> [ 74.783533][ T2158] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
>> [ 74.784010][ T2158] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000105f34000
>> [ 74.784586][ T2158] [0000000000000020] pgd=0000000000000000, p4d=0000000000000000
>> [ 74.785293][ T2158] Internal error: Oops: 0000000096000004 [#1] SMP
>> [ 74.785805][ T2158] Modules linked in: slub_kunit kunit ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute ip6table_nat ip6table_mangle 4
>> [ 74.790661][ T2158] CPU: 0 UID: 0 PID: 2158 Comm: kunit_try_catch Kdump: loaded Tainted: G W N 6.12.0-rc3+ #2
>> [ 74.791535][ T2158] Tainted: [W]=WARN, [N]=TEST
>> [ 74.791889][ T2158] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
>> [ 74.792479][ T2158] pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
>> [ 74.793101][ T2158] pc : alloc_tagging_slab_alloc_hook+0x120/0x270
>> [ 74.793607][ T2158] lr : alloc_tagging_slab_alloc_hook+0x120/0x270
>>
>> [ 74.794095][ T2158] sp : ffff800084d33cd0
>> [ 74.794418][ T2158] x29: ffff800084d33cd0 x28: 0000000000000000 x27: 0000000000000000
>> [ 74.795095][ T2158] x26: 0000000000000000 x25: 0000000000000012 x24: ffff80007b30e314
>> [ 74.795822][ T2158] x23: ffff000390ff6f10 x22: 0000000000000000 x21: 0000000000000088
>> [ 74.796555][ T2158] x20: ffff000390285840 x19: fffffd7fc3ef7830 x18: ffffffffffffffff
>> [ 74.797283][ T2158] x17: ffff8000800e63b4 x16: ffff80007b33afc4 x15: ffff800081654c00
>> [ 74.798011][ T2158] x14: 0000000000000000 x13: 205d383531325420 x12: 5b5d383734363537
>> [ 74.798744][ T2158] x11: ffff800084d337e0 x10: 000000000000005d x9 : 00000000ffffffd0
>> [ 74.799476][ T2158] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008219d188 x6 : c0000000ffff7fff
>> [ 74.800206][ T2158] x5 : ffff0003fdbc9208 x4 : ffff800081edd188 x3 : 0000000000000001
>> [ 74.800932][ T2158] x2 : 0beaa6dee1ac5a00 x1 : 0beaa6dee1ac5a00 x0 : ffff80037c2cb000
>> [ 74.801656][ T2158] Call trace:
>> [ 74.801954][ T2158] alloc_tagging_slab_alloc_hook+0x120/0x270
>> [ 74.802494][ T2158] __kmalloc_cache_noprof+0x148/0x33c
>> [ 74.802976][ T2158] test_kmalloc_redzone_access+0x4c/0x104 [slub_kunit]
>> [ 74.803607][ T2158] kunit_try_run_case+0x70/0x17c [kunit]
>> [ 74.804124][ T2158] kunit_generic_run_threadfn_adapter+0x2c/0x4c [kunit]
>> [ 74.804768][ T2158] kthread+0x10c/0x118
>> [ 74.805141][ T2158] ret_from_fork+0x10/0x20
>> [ 74.805540][ T2158] Code: b9400a80 11000400 b9000a80 97ffd858 (f94012d3)
>> [ 74.806176][ T2158] SMP: stopping secondary CPUs
>> [ 74.808130][ T2158] Starting crashdump kernel...
>>
> CC'ing Vlastimil.
> This patch essentially reverts Vlastimil's "mm, slab: don't wrap
> internal functions with alloc_hooks()" change. Please check why that
> change was needed before proceeding.
> If this change is indeed needed, please add:
Hi Suren and Vlastimil
In fact, besides the panic, there is also a warning here due to directly
invoking__kmalloc_cache_noprof
Regarding this, do you have any suggestions?
[58162.947016] WARNING: CPU: 2 PID: 6210 at
./include/linux/alloc_tag.h:125 alloc_tagging_slab_alloc_hook+0x268/0x27c
[58162.957721] Call trace:
[58162.957919] alloc_tagging_slab_alloc_hook+0x268/0x27c
[58162.958286] __kmalloc_cache_noprof+0x14c/0x344
[58162.958615] test_kmalloc_redzone_access+0x50/0x10c [slub_kunit]
[58162.959045] kunit_try_run_case+0x74/0x184 [kunit]
[58162.959401] kunit_generic_run_threadfn_adapter+0x2c/0x4c [kunit]
[58162.959841] kthread+0x10c/0x118
[58162.960093] ret_from_fork+0x10/0x20
[58162.960363] ---[ end trace 0000000000000000 ]---
Thanks
Best regards
Hao
>
> Fixes: a0a44d9175b349 ("mm, slab: don't wrap internal functions with
> alloc_hooks()")
>
>> Signed-off-by: Pei Xiao <xiaopei01@kylinos.cn>
>> ---
>> include/linux/slab.h | 1 +
>> lib/slub_kunit.c | 2 +-
>> 2 files changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/include/linux/slab.h b/include/linux/slab.h
>> index 10a971c2bde3..0149d36cd311 100644
>> --- a/include/linux/slab.h
>> +++ b/include/linux/slab.h
>> @@ -827,6 +827,7 @@ void *__kmalloc_cache_noprof(struct kmem_cache *s, gfp_t flags, size_t size)
>> void *__kmalloc_cache_node_noprof(struct kmem_cache *s, gfp_t gfpflags,
>> int node, size_t size)
>> __assume_kmalloc_alignment __alloc_size(4);
>> +#define kmalloc_cache(...) alloc_hooks(__kmalloc_cache_noprof(__VA_ARGS__))
>>
>> void *__kmalloc_large_noprof(size_t size, gfp_t flags)
>> __assume_page_alignment __alloc_size(1);
>> diff --git a/lib/slub_kunit.c b/lib/slub_kunit.c
>> index 80e39f003344..4bf38f52dbbd 100644
>> --- a/lib/slub_kunit.c
>> +++ b/lib/slub_kunit.c
>> @@ -141,7 +141,7 @@ static void test_kmalloc_redzone_access(struct kunit *test)
>> {
>> struct kmem_cache *s = test_kmem_cache_create("TestSlub_RZ_kmalloc", 32,
>> SLAB_KMALLOC|SLAB_STORE_USER|SLAB_RED_ZONE);
>> - u8 *p = __kmalloc_cache_noprof(s, GFP_KERNEL, 18);
>> + u8 *p = kmalloc_cache(s, GFP_KERNEL, 18);
>>
>> kasan_disable_current();
>>
>> --
>> 2.34.1
>>
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] slub/slub_kunit:fix a panic due to __kmalloc_cache_noprof incorretly use
2024-10-22 2:19 ` Hao Ge
@ 2024-10-22 15:27 ` Vlastimil Babka
2024-10-23 1:47 ` Hao Ge
0 siblings, 1 reply; 8+ messages in thread
From: Vlastimil Babka @ 2024-10-22 15:27 UTC (permalink / raw)
To: Hao Ge, Suren Baghdasaryan, xiaopeitux
Cc: akpm, linux-kernel, linux-mm, yuzhao, xiaopei01, gehao, xiongxin
On 10/22/24 04:19, Hao Ge wrote:
>
> On 10/22/24 01:42, Suren Baghdasaryan wrote:
>> On Sun, Oct 20, 2024 at 11:59 PM <xiaopeitux@foxmail.com> wrote:
>>> From: Pei Xiao <xiaopei01@kylinos.cn>
>>>
>>> 'modprobe slub_kunit',will have a panic.The root cause is that
>>> __kmalloc_cache_noprof was directly ,which resulted in no alloc_tag
>>> being allocated.This caused current->alloc_tag to be null,leading to
>>> a null pointer dereference in alloc_tag_ref_set.
>> I think the root cause of this crash is the bug that is fixed by
>> https://lore.kernel.org/all/20241020070819.307944-1-hao.ge@linux.dev/.
>> Do you get this crash if you apply that fix?
> Yes, this patch has resolved the panic issue.
>>> Here is the log for the panic:
>>> [ 74.779373][ T2158] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
>>> [ 74.780130][ T2158] Mem abort info:
>>> [ 74.780406][ T2158] ESR = 0x0000000096000004
>>> [ 74.780756][ T2158] EC = 0x25: DABT (current EL), IL = 32 bits
>>> [ 74.781225][ T2158] SET = 0, FnV = 0
>>> [ 74.781529][ T2158] EA = 0, S1PTW = 0
>>> [ 74.781836][ T2158] FSC = 0x04: level 0 translation fault
>>> [ 74.782288][ T2158] Data abort info:
>>> [ 74.782577][ T2158] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
>>> [ 74.783068][ T2158] CM = 0, WnR = 0, TnD = 0, TagAccess = 0
>>> [ 74.783533][ T2158] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
>>> [ 74.784010][ T2158] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000105f34000
>>> [ 74.784586][ T2158] [0000000000000020] pgd=0000000000000000, p4d=0000000000000000
>>> [ 74.785293][ T2158] Internal error: Oops: 0000000096000004 [#1] SMP
>>> [ 74.785805][ T2158] Modules linked in: slub_kunit kunit ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute ip6table_nat ip6table_mangle 4
>>> [ 74.790661][ T2158] CPU: 0 UID: 0 PID: 2158 Comm: kunit_try_catch Kdump: loaded Tainted: G W N 6.12.0-rc3+ #2
>>> [ 74.791535][ T2158] Tainted: [W]=WARN, [N]=TEST
>>> [ 74.791889][ T2158] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
>>> [ 74.792479][ T2158] pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
>>> [ 74.793101][ T2158] pc : alloc_tagging_slab_alloc_hook+0x120/0x270
>>> [ 74.793607][ T2158] lr : alloc_tagging_slab_alloc_hook+0x120/0x270
>>>
>>> [ 74.794095][ T2158] sp : ffff800084d33cd0
>>> [ 74.794418][ T2158] x29: ffff800084d33cd0 x28: 0000000000000000 x27: 0000000000000000
>>> [ 74.795095][ T2158] x26: 0000000000000000 x25: 0000000000000012 x24: ffff80007b30e314
>>> [ 74.795822][ T2158] x23: ffff000390ff6f10 x22: 0000000000000000 x21: 0000000000000088
>>> [ 74.796555][ T2158] x20: ffff000390285840 x19: fffffd7fc3ef7830 x18: ffffffffffffffff
>>> [ 74.797283][ T2158] x17: ffff8000800e63b4 x16: ffff80007b33afc4 x15: ffff800081654c00
>>> [ 74.798011][ T2158] x14: 0000000000000000 x13: 205d383531325420 x12: 5b5d383734363537
>>> [ 74.798744][ T2158] x11: ffff800084d337e0 x10: 000000000000005d x9 : 00000000ffffffd0
>>> [ 74.799476][ T2158] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008219d188 x6 : c0000000ffff7fff
>>> [ 74.800206][ T2158] x5 : ffff0003fdbc9208 x4 : ffff800081edd188 x3 : 0000000000000001
>>> [ 74.800932][ T2158] x2 : 0beaa6dee1ac5a00 x1 : 0beaa6dee1ac5a00 x0 : ffff80037c2cb000
>>> [ 74.801656][ T2158] Call trace:
>>> [ 74.801954][ T2158] alloc_tagging_slab_alloc_hook+0x120/0x270
>>> [ 74.802494][ T2158] __kmalloc_cache_noprof+0x148/0x33c
>>> [ 74.802976][ T2158] test_kmalloc_redzone_access+0x4c/0x104 [slub_kunit]
>>> [ 74.803607][ T2158] kunit_try_run_case+0x70/0x17c [kunit]
>>> [ 74.804124][ T2158] kunit_generic_run_threadfn_adapter+0x2c/0x4c [kunit]
>>> [ 74.804768][ T2158] kthread+0x10c/0x118
>>> [ 74.805141][ T2158] ret_from_fork+0x10/0x20
>>> [ 74.805540][ T2158] Code: b9400a80 11000400 b9000a80 97ffd858 (f94012d3)
>>> [ 74.806176][ T2158] SMP: stopping secondary CPUs
>>> [ 74.808130][ T2158] Starting crashdump kernel...
>>>
>> CC'ing Vlastimil.
>> This patch essentially reverts Vlastimil's "mm, slab: don't wrap
>> internal functions with alloc_hooks()" change. Please check why that
>> change was needed before proceeding.
>> If this change is indeed needed, please add:
>
> Hi Suren and Vlastimil
>
> In fact, besides the panic, there is also a warning here due to directly
> invoking__kmalloc_cache_noprof
>
> Regarding this, do you have any suggestions?
>
> [58162.947016] WARNING: CPU: 2 PID: 6210 at
> ./include/linux/alloc_tag.h:125 alloc_tagging_slab_alloc_hook+0x268/0x27c
> [58162.957721] Call trace:
> [58162.957919] alloc_tagging_slab_alloc_hook+0x268/0x27c
> [58162.958286] __kmalloc_cache_noprof+0x14c/0x344
> [58162.958615] test_kmalloc_redzone_access+0x50/0x10c [slub_kunit]
> [58162.959045] kunit_try_run_case+0x74/0x184 [kunit]
> [58162.959401] kunit_generic_run_threadfn_adapter+0x2c/0x4c [kunit]
> [58162.959841] kthread+0x10c/0x118
> [58162.960093] ret_from_fork+0x10/0x20
> [58162.960363] ---[ end trace 0000000000000000 ]---
I see.
The kunit test is the only user of __kmalloc_cache_noprof outside of kmalloc()
itself so it's not worth defining again a wrapper for everyone, how about just
wrapping the two callsites?
--- a/lib/slub_kunit.c
+++ b/lib/slub_kunit.c
@@ -141,7 +141,7 @@ static void test_kmalloc_redzone_access(struct kunit *test)
{
struct kmem_cache *s = test_kmem_cache_create("TestSlub_RZ_kmalloc", 32,
SLAB_KMALLOC|SLAB_STORE_USER|SLAB_RED_ZONE);
- u8 *p = __kmalloc_cache_noprof(s, GFP_KERNEL, 18);
+ u8 *p = alloc_hooks(__kmalloc_cache_noprof(s, GFP_KERNEL, 18));
kasan_disable_current();
@@ -199,7 +199,7 @@ static void test_krealloc_redzone_zeroing(struct kunit *test)
struct kmem_cache *s = test_kmem_cache_create("TestSlub_krealloc", 64,
SLAB_KMALLOC|SLAB_STORE_USER|SLAB_RED_ZONE);
- p = __kmalloc_cache_noprof(s, GFP_KERNEL, 48);
+ p = alloc_hooks(__kmalloc_cache_noprof(s, GFP_KERNEL, 48));
memset(p, 0xff, 48);
kasan_disable_current();
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] slub/slub_kunit:fix a panic due to __kmalloc_cache_noprof incorretly use
2024-10-22 15:27 ` Vlastimil Babka
@ 2024-10-23 1:47 ` Hao Ge
2024-10-23 1:58 ` Suren Baghdasaryan
0 siblings, 1 reply; 8+ messages in thread
From: Hao Ge @ 2024-10-23 1:47 UTC (permalink / raw)
To: Vlastimil Babka, Suren Baghdasaryan, xiaopeitux
Cc: akpm, linux-kernel, linux-mm, yuzhao, xiaopei01, gehao, xiongxin
On 10/22/24 23:27, Vlastimil Babka wrote:
> On 10/22/24 04:19, Hao Ge wrote:
>> On 10/22/24 01:42, Suren Baghdasaryan wrote:
>>> On Sun, Oct 20, 2024 at 11:59 PM <xiaopeitux@foxmail.com> wrote:
>>>> From: Pei Xiao <xiaopei01@kylinos.cn>
>>>>
>>>> 'modprobe slub_kunit',will have a panic.The root cause is that
>>>> __kmalloc_cache_noprof was directly ,which resulted in no alloc_tag
>>>> being allocated.This caused current->alloc_tag to be null,leading to
>>>> a null pointer dereference in alloc_tag_ref_set.
>>> I think the root cause of this crash is the bug that is fixed by
>>> https://lore.kernel.org/all/20241020070819.307944-1-hao.ge@linux.dev/.
>>> Do you get this crash if you apply that fix?
>> Yes, this patch has resolved the panic issue.
>>>> Here is the log for the panic:
>>>> [ 74.779373][ T2158] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
>>>> [ 74.780130][ T2158] Mem abort info:
>>>> [ 74.780406][ T2158] ESR = 0x0000000096000004
>>>> [ 74.780756][ T2158] EC = 0x25: DABT (current EL), IL = 32 bits
>>>> [ 74.781225][ T2158] SET = 0, FnV = 0
>>>> [ 74.781529][ T2158] EA = 0, S1PTW = 0
>>>> [ 74.781836][ T2158] FSC = 0x04: level 0 translation fault
>>>> [ 74.782288][ T2158] Data abort info:
>>>> [ 74.782577][ T2158] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
>>>> [ 74.783068][ T2158] CM = 0, WnR = 0, TnD = 0, TagAccess = 0
>>>> [ 74.783533][ T2158] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
>>>> [ 74.784010][ T2158] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000105f34000
>>>> [ 74.784586][ T2158] [0000000000000020] pgd=0000000000000000, p4d=0000000000000000
>>>> [ 74.785293][ T2158] Internal error: Oops: 0000000096000004 [#1] SMP
>>>> [ 74.785805][ T2158] Modules linked in: slub_kunit kunit ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute ip6table_nat ip6table_mangle 4
>>>> [ 74.790661][ T2158] CPU: 0 UID: 0 PID: 2158 Comm: kunit_try_catch Kdump: loaded Tainted: G W N 6.12.0-rc3+ #2
>>>> [ 74.791535][ T2158] Tainted: [W]=WARN, [N]=TEST
>>>> [ 74.791889][ T2158] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
>>>> [ 74.792479][ T2158] pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
>>>> [ 74.793101][ T2158] pc : alloc_tagging_slab_alloc_hook+0x120/0x270
>>>> [ 74.793607][ T2158] lr : alloc_tagging_slab_alloc_hook+0x120/0x270
>>>>
>>>> [ 74.794095][ T2158] sp : ffff800084d33cd0
>>>> [ 74.794418][ T2158] x29: ffff800084d33cd0 x28: 0000000000000000 x27: 0000000000000000
>>>> [ 74.795095][ T2158] x26: 0000000000000000 x25: 0000000000000012 x24: ffff80007b30e314
>>>> [ 74.795822][ T2158] x23: ffff000390ff6f10 x22: 0000000000000000 x21: 0000000000000088
>>>> [ 74.796555][ T2158] x20: ffff000390285840 x19: fffffd7fc3ef7830 x18: ffffffffffffffff
>>>> [ 74.797283][ T2158] x17: ffff8000800e63b4 x16: ffff80007b33afc4 x15: ffff800081654c00
>>>> [ 74.798011][ T2158] x14: 0000000000000000 x13: 205d383531325420 x12: 5b5d383734363537
>>>> [ 74.798744][ T2158] x11: ffff800084d337e0 x10: 000000000000005d x9 : 00000000ffffffd0
>>>> [ 74.799476][ T2158] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008219d188 x6 : c0000000ffff7fff
>>>> [ 74.800206][ T2158] x5 : ffff0003fdbc9208 x4 : ffff800081edd188 x3 : 0000000000000001
>>>> [ 74.800932][ T2158] x2 : 0beaa6dee1ac5a00 x1 : 0beaa6dee1ac5a00 x0 : ffff80037c2cb000
>>>> [ 74.801656][ T2158] Call trace:
>>>> [ 74.801954][ T2158] alloc_tagging_slab_alloc_hook+0x120/0x270
>>>> [ 74.802494][ T2158] __kmalloc_cache_noprof+0x148/0x33c
>>>> [ 74.802976][ T2158] test_kmalloc_redzone_access+0x4c/0x104 [slub_kunit]
>>>> [ 74.803607][ T2158] kunit_try_run_case+0x70/0x17c [kunit]
>>>> [ 74.804124][ T2158] kunit_generic_run_threadfn_adapter+0x2c/0x4c [kunit]
>>>> [ 74.804768][ T2158] kthread+0x10c/0x118
>>>> [ 74.805141][ T2158] ret_from_fork+0x10/0x20
>>>> [ 74.805540][ T2158] Code: b9400a80 11000400 b9000a80 97ffd858 (f94012d3)
>>>> [ 74.806176][ T2158] SMP: stopping secondary CPUs
>>>> [ 74.808130][ T2158] Starting crashdump kernel...
>>>>
>>> CC'ing Vlastimil.
>>> This patch essentially reverts Vlastimil's "mm, slab: don't wrap
>>> internal functions with alloc_hooks()" change. Please check why that
>>> change was needed before proceeding.
>>> If this change is indeed needed, please add:
>> Hi Suren and Vlastimil
>>
>> In fact, besides the panic, there is also a warning here due to directly
>> invoking__kmalloc_cache_noprof
>>
>> Regarding this, do you have any suggestions?
>>
>> [58162.947016] WARNING: CPU: 2 PID: 6210 at
>> ./include/linux/alloc_tag.h:125 alloc_tagging_slab_alloc_hook+0x268/0x27c
>> [58162.957721] Call trace:
>> [58162.957919] alloc_tagging_slab_alloc_hook+0x268/0x27c
>> [58162.958286] __kmalloc_cache_noprof+0x14c/0x344
>> [58162.958615] test_kmalloc_redzone_access+0x50/0x10c [slub_kunit]
>> [58162.959045] kunit_try_run_case+0x74/0x184 [kunit]
>> [58162.959401] kunit_generic_run_threadfn_adapter+0x2c/0x4c [kunit]
>> [58162.959841] kthread+0x10c/0x118
>> [58162.960093] ret_from_fork+0x10/0x20
>> [58162.960363] ---[ end trace 0000000000000000 ]---
> I see.
> The kunit test is the only user of __kmalloc_cache_noprof outside of kmalloc()
> itself so it's not worth defining again a wrapper for everyone, how about just
> wrapping the two callsites?
>
> --- a/lib/slub_kunit.c
> +++ b/lib/slub_kunit.c
> @@ -141,7 +141,7 @@ static void test_kmalloc_redzone_access(struct kunit *test)
> {
> struct kmem_cache *s = test_kmem_cache_create("TestSlub_RZ_kmalloc", 32,
> SLAB_KMALLOC|SLAB_STORE_USER|SLAB_RED_ZONE);
> - u8 *p = __kmalloc_cache_noprof(s, GFP_KERNEL, 18);
> + u8 *p = alloc_hooks(__kmalloc_cache_noprof(s, GFP_KERNEL, 18));
>
> kasan_disable_current();
>
> @@ -199,7 +199,7 @@ static void test_krealloc_redzone_zeroing(struct kunit *test)
> struct kmem_cache *s = test_kmem_cache_create("TestSlub_krealloc", 64,
> SLAB_KMALLOC|SLAB_STORE_USER|SLAB_RED_ZONE);
>
> - p = __kmalloc_cache_noprof(s, GFP_KERNEL, 48);
> + p = alloc_hooks(__kmalloc_cache_noprof(s, GFP_KERNEL, 48));
> memset(p, 0xff, 48);
>
> kasan_disable_current();
>
Hi Vlastimil
I agree with your point of view, thank you for you and Suren's help and
suggestion.
Best regards
Hao
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] slub/slub_kunit:fix a panic due to __kmalloc_cache_noprof incorretly use
2024-10-23 1:47 ` Hao Ge
@ 2024-10-23 1:58 ` Suren Baghdasaryan
2024-10-23 6:21 ` [PATCH] slub_kunit:fix a WARNING " Pei Xiao
0 siblings, 1 reply; 8+ messages in thread
From: Suren Baghdasaryan @ 2024-10-23 1:58 UTC (permalink / raw)
To: Hao Ge
Cc: Vlastimil Babka, xiaopeitux, akpm, linux-kernel, linux-mm,
yuzhao, xiaopei01, gehao, xiongxin
On Tue, Oct 22, 2024 at 6:47 PM Hao Ge <hao.ge@linux.dev> wrote:
>
>
> On 10/22/24 23:27, Vlastimil Babka wrote:
> > On 10/22/24 04:19, Hao Ge wrote:
> >> On 10/22/24 01:42, Suren Baghdasaryan wrote:
> >>> On Sun, Oct 20, 2024 at 11:59 PM <xiaopeitux@foxmail.com> wrote:
> >>>> From: Pei Xiao <xiaopei01@kylinos.cn>
> >>>>
> >>>> 'modprobe slub_kunit',will have a panic.The root cause is that
> >>>> __kmalloc_cache_noprof was directly ,which resulted in no alloc_tag
> >>>> being allocated.This caused current->alloc_tag to be null,leading to
> >>>> a null pointer dereference in alloc_tag_ref_set.
> >>> I think the root cause of this crash is the bug that is fixed by
> >>> https://lore.kernel.org/all/20241020070819.307944-1-hao.ge@linux.dev/.
> >>> Do you get this crash if you apply that fix?
> >> Yes, this patch has resolved the panic issue.
> >>>> Here is the log for the panic:
> >>>> [ 74.779373][ T2158] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
> >>>> [ 74.780130][ T2158] Mem abort info:
> >>>> [ 74.780406][ T2158] ESR = 0x0000000096000004
> >>>> [ 74.780756][ T2158] EC = 0x25: DABT (current EL), IL = 32 bits
> >>>> [ 74.781225][ T2158] SET = 0, FnV = 0
> >>>> [ 74.781529][ T2158] EA = 0, S1PTW = 0
> >>>> [ 74.781836][ T2158] FSC = 0x04: level 0 translation fault
> >>>> [ 74.782288][ T2158] Data abort info:
> >>>> [ 74.782577][ T2158] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
> >>>> [ 74.783068][ T2158] CM = 0, WnR = 0, TnD = 0, TagAccess = 0
> >>>> [ 74.783533][ T2158] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
> >>>> [ 74.784010][ T2158] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000105f34000
> >>>> [ 74.784586][ T2158] [0000000000000020] pgd=0000000000000000, p4d=0000000000000000
> >>>> [ 74.785293][ T2158] Internal error: Oops: 0000000096000004 [#1] SMP
> >>>> [ 74.785805][ T2158] Modules linked in: slub_kunit kunit ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute ip6table_nat ip6table_mangle 4
> >>>> [ 74.790661][ T2158] CPU: 0 UID: 0 PID: 2158 Comm: kunit_try_catch Kdump: loaded Tainted: G W N 6.12.0-rc3+ #2
> >>>> [ 74.791535][ T2158] Tainted: [W]=WARN, [N]=TEST
> >>>> [ 74.791889][ T2158] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
> >>>> [ 74.792479][ T2158] pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> >>>> [ 74.793101][ T2158] pc : alloc_tagging_slab_alloc_hook+0x120/0x270
> >>>> [ 74.793607][ T2158] lr : alloc_tagging_slab_alloc_hook+0x120/0x270
> >>>>
> >>>> [ 74.794095][ T2158] sp : ffff800084d33cd0
> >>>> [ 74.794418][ T2158] x29: ffff800084d33cd0 x28: 0000000000000000 x27: 0000000000000000
> >>>> [ 74.795095][ T2158] x26: 0000000000000000 x25: 0000000000000012 x24: ffff80007b30e314
> >>>> [ 74.795822][ T2158] x23: ffff000390ff6f10 x22: 0000000000000000 x21: 0000000000000088
> >>>> [ 74.796555][ T2158] x20: ffff000390285840 x19: fffffd7fc3ef7830 x18: ffffffffffffffff
> >>>> [ 74.797283][ T2158] x17: ffff8000800e63b4 x16: ffff80007b33afc4 x15: ffff800081654c00
> >>>> [ 74.798011][ T2158] x14: 0000000000000000 x13: 205d383531325420 x12: 5b5d383734363537
> >>>> [ 74.798744][ T2158] x11: ffff800084d337e0 x10: 000000000000005d x9 : 00000000ffffffd0
> >>>> [ 74.799476][ T2158] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008219d188 x6 : c0000000ffff7fff
> >>>> [ 74.800206][ T2158] x5 : ffff0003fdbc9208 x4 : ffff800081edd188 x3 : 0000000000000001
> >>>> [ 74.800932][ T2158] x2 : 0beaa6dee1ac5a00 x1 : 0beaa6dee1ac5a00 x0 : ffff80037c2cb000
> >>>> [ 74.801656][ T2158] Call trace:
> >>>> [ 74.801954][ T2158] alloc_tagging_slab_alloc_hook+0x120/0x270
> >>>> [ 74.802494][ T2158] __kmalloc_cache_noprof+0x148/0x33c
> >>>> [ 74.802976][ T2158] test_kmalloc_redzone_access+0x4c/0x104 [slub_kunit]
> >>>> [ 74.803607][ T2158] kunit_try_run_case+0x70/0x17c [kunit]
> >>>> [ 74.804124][ T2158] kunit_generic_run_threadfn_adapter+0x2c/0x4c [kunit]
> >>>> [ 74.804768][ T2158] kthread+0x10c/0x118
> >>>> [ 74.805141][ T2158] ret_from_fork+0x10/0x20
> >>>> [ 74.805540][ T2158] Code: b9400a80 11000400 b9000a80 97ffd858 (f94012d3)
> >>>> [ 74.806176][ T2158] SMP: stopping secondary CPUs
> >>>> [ 74.808130][ T2158] Starting crashdump kernel...
> >>>>
> >>> CC'ing Vlastimil.
> >>> This patch essentially reverts Vlastimil's "mm, slab: don't wrap
> >>> internal functions with alloc_hooks()" change. Please check why that
> >>> change was needed before proceeding.
> >>> If this change is indeed needed, please add:
> >> Hi Suren and Vlastimil
> >>
> >> In fact, besides the panic, there is also a warning here due to directly
> >> invoking__kmalloc_cache_noprof
> >>
> >> Regarding this, do you have any suggestions?
> >>
> >> [58162.947016] WARNING: CPU: 2 PID: 6210 at
> >> ./include/linux/alloc_tag.h:125 alloc_tagging_slab_alloc_hook+0x268/0x27c
> >> [58162.957721] Call trace:
> >> [58162.957919] alloc_tagging_slab_alloc_hook+0x268/0x27c
> >> [58162.958286] __kmalloc_cache_noprof+0x14c/0x344
> >> [58162.958615] test_kmalloc_redzone_access+0x50/0x10c [slub_kunit]
> >> [58162.959045] kunit_try_run_case+0x74/0x184 [kunit]
> >> [58162.959401] kunit_generic_run_threadfn_adapter+0x2c/0x4c [kunit]
> >> [58162.959841] kthread+0x10c/0x118
> >> [58162.960093] ret_from_fork+0x10/0x20
> >> [58162.960363] ---[ end trace 0000000000000000 ]---
> > I see.
> > The kunit test is the only user of __kmalloc_cache_noprof outside of kmalloc()
> > itself so it's not worth defining again a wrapper for everyone, how about just
> > wrapping the two callsites?
> >
> > --- a/lib/slub_kunit.c
> > +++ b/lib/slub_kunit.c
> > @@ -141,7 +141,7 @@ static void test_kmalloc_redzone_access(struct kunit *test)
> > {
> > struct kmem_cache *s = test_kmem_cache_create("TestSlub_RZ_kmalloc", 32,
> > SLAB_KMALLOC|SLAB_STORE_USER|SLAB_RED_ZONE);
> > - u8 *p = __kmalloc_cache_noprof(s, GFP_KERNEL, 18);
> > + u8 *p = alloc_hooks(__kmalloc_cache_noprof(s, GFP_KERNEL, 18));
> >
> > kasan_disable_current();
> >
> > @@ -199,7 +199,7 @@ static void test_krealloc_redzone_zeroing(struct kunit *test)
> > struct kmem_cache *s = test_kmem_cache_create("TestSlub_krealloc", 64,
> > SLAB_KMALLOC|SLAB_STORE_USER|SLAB_RED_ZONE);
> >
> > - p = __kmalloc_cache_noprof(s, GFP_KERNEL, 48);
> > + p = alloc_hooks(__kmalloc_cache_noprof(s, GFP_KERNEL, 48));
> > memset(p, 0xff, 48);
> >
> > kasan_disable_current();
> >
> Hi Vlastimil
>
> I agree with your point of view, thank you for you and Suren's help and
> suggestion.
That seems reasonable to me. Thanks!
>
> Best regards
>
> Hao
>
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH] slub_kunit:fix a WARNING due to __kmalloc_cache_noprof incorretly use
2024-10-23 1:58 ` Suren Baghdasaryan
@ 2024-10-23 6:21 ` Pei Xiao
2024-10-23 8:00 ` Vlastimil Babka
0 siblings, 1 reply; 8+ messages in thread
From: Pei Xiao @ 2024-10-23 6:21 UTC (permalink / raw)
To: surenb
Cc: akpm, gehao, hao.ge, linux-kernel, linux-mm, vbabka, xiaopei01,
xiaopeitux, xiongxin, yuzhao
'modprobe slub_kunit',will have a warning [1].The root cause is that
__kmalloc_cache_noprof was directly used,which resulted in no alloc_tag
being allocated.This caused current->alloc_tag to be null,leading to
a warning in alloc_tag_add_check.
Let's add an alloc_hook layer to __kmalloc_cache_noprof specifically
within lib/slub_kunit.c.
[1].
[58162.947016] WARNING: CPU: 2 PID: 6210 at
./include/linux/alloc_tag.h:125 alloc_tagging_slab_alloc_hook+0x268/0x27c
[58162.957721] Call trace:
[58162.957919] alloc_tagging_slab_alloc_hook+0x268/0x27c
[58162.958286] __kmalloc_cache_noprof+0x14c/0x344
[58162.958615] test_kmalloc_redzone_access+0x50/0x10c [slub_kunit]
[58162.959045] kunit_try_run_case+0x74/0x184 [kunit]
[58162.959401] kunit_generic_run_threadfn_adapter+0x2c/0x4c [kunit]
[58162.959841] kthread+0x10c/0x118
[58162.960093] ret_from_fork+0x10/0x20
[58162.960363] ---[ end trace 0000000000000000 ]---
Signed-off-by: Pei Xiao <xiaopei01@kylinos.cn>
Fixes: a0a44d9175b3 ("mm, slab: don't wrap internal functions with alloc_hooks()")
Fixes: a286da323418 ("mm/slub, kunit: Add testcase for krealloc redzone and zeroing")
---
lib/slub_kunit.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/lib/slub_kunit.c b/lib/slub_kunit.c
index 3cd1cc667988..f11691315c2f 100644
--- a/lib/slub_kunit.c
+++ b/lib/slub_kunit.c
@@ -141,7 +141,7 @@ static void test_kmalloc_redzone_access(struct kunit *test)
{
struct kmem_cache *s = test_kmem_cache_create("TestSlub_RZ_kmalloc", 32,
SLAB_KMALLOC|SLAB_STORE_USER|SLAB_RED_ZONE);
- u8 *p = __kmalloc_cache_noprof(s, GFP_KERNEL, 18);
+ u8 *p = alloc_hooks(__kmalloc_cache_noprof(s, GFP_KERNEL, 18));
kasan_disable_current();
@@ -199,7 +199,7 @@ static void test_krealloc_redzone_zeroing(struct kunit *test)
struct kmem_cache *s = test_kmem_cache_create("TestSlub_krealloc", 64,
SLAB_KMALLOC|SLAB_STORE_USER|SLAB_RED_ZONE);
- p = __kmalloc_cache_noprof(s, GFP_KERNEL, 48);
+ p = alloc_hooks(__kmalloc_cache_noprof(s, GFP_KERNEL, 48));
memset(p, 0xff, 48);
kasan_disable_current();
--
2.34.1
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] slub_kunit:fix a WARNING due to __kmalloc_cache_noprof incorretly use
2024-10-23 6:21 ` [PATCH] slub_kunit:fix a WARNING " Pei Xiao
@ 2024-10-23 8:00 ` Vlastimil Babka
0 siblings, 0 replies; 8+ messages in thread
From: Vlastimil Babka @ 2024-10-23 8:00 UTC (permalink / raw)
To: Pei Xiao, surenb
Cc: akpm, gehao, hao.ge, linux-kernel, linux-mm, xiaopeitux,
xiongxin, yuzhao
On 10/23/24 08:21, Pei Xiao wrote:
> 'modprobe slub_kunit',will have a warning [1].The root cause is that
> __kmalloc_cache_noprof was directly used,which resulted in no alloc_tag
> being allocated.This caused current->alloc_tag to be null,leading to
> a warning in alloc_tag_add_check.
>
> Let's add an alloc_hook layer to __kmalloc_cache_noprof specifically
> within lib/slub_kunit.c.
>
> [1].
> [58162.947016] WARNING: CPU: 2 PID: 6210 at
> ./include/linux/alloc_tag.h:125 alloc_tagging_slab_alloc_hook+0x268/0x27c
> [58162.957721] Call trace:
> [58162.957919] alloc_tagging_slab_alloc_hook+0x268/0x27c
> [58162.958286] __kmalloc_cache_noprof+0x14c/0x344
> [58162.958615] test_kmalloc_redzone_access+0x50/0x10c [slub_kunit]
> [58162.959045] kunit_try_run_case+0x74/0x184 [kunit]
> [58162.959401] kunit_generic_run_threadfn_adapter+0x2c/0x4c [kunit]
> [58162.959841] kthread+0x10c/0x118
> [58162.960093] ret_from_fork+0x10/0x20
> [58162.960363] ---[ end trace 0000000000000000 ]---
>
> Signed-off-by: Pei Xiao <xiaopei01@kylinos.cn>
> Fixes: a0a44d9175b3 ("mm, slab: don't wrap internal functions with alloc_hooks()")
Thanks, I'm adding the fix for test_kmalloc_redzone_access() to
slab/for-6.12-rc4/fixes as a 6.12 hotfix
> Fixes: a286da323418 ("mm/slub, kunit: Add testcase for krealloc redzone and zeroing")
This is in slab/for-next so I will just adjust the new tests in place there.
> ---
> lib/slub_kunit.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/lib/slub_kunit.c b/lib/slub_kunit.c
> index 3cd1cc667988..f11691315c2f 100644
> --- a/lib/slub_kunit.c
> +++ b/lib/slub_kunit.c
> @@ -141,7 +141,7 @@ static void test_kmalloc_redzone_access(struct kunit *test)
> {
> struct kmem_cache *s = test_kmem_cache_create("TestSlub_RZ_kmalloc", 32,
> SLAB_KMALLOC|SLAB_STORE_USER|SLAB_RED_ZONE);
> - u8 *p = __kmalloc_cache_noprof(s, GFP_KERNEL, 18);
> + u8 *p = alloc_hooks(__kmalloc_cache_noprof(s, GFP_KERNEL, 18));
>
> kasan_disable_current();
>
> @@ -199,7 +199,7 @@ static void test_krealloc_redzone_zeroing(struct kunit *test)
> struct kmem_cache *s = test_kmem_cache_create("TestSlub_krealloc", 64,
> SLAB_KMALLOC|SLAB_STORE_USER|SLAB_RED_ZONE);
>
> - p = __kmalloc_cache_noprof(s, GFP_KERNEL, 48);
> + p = alloc_hooks(__kmalloc_cache_noprof(s, GFP_KERNEL, 48));
> memset(p, 0xff, 48);
>
> kasan_disable_current();
^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2024-10-23 8:00 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2024-10-21 6:59 [PATCH] slub/slub_kunit:fix a panic due to __kmalloc_cache_noprof incorretly use xiaopeitux
2024-10-21 17:42 ` Suren Baghdasaryan
2024-10-22 2:19 ` Hao Ge
2024-10-22 15:27 ` Vlastimil Babka
2024-10-23 1:47 ` Hao Ge
2024-10-23 1:58 ` Suren Baghdasaryan
2024-10-23 6:21 ` [PATCH] slub_kunit:fix a WARNING " Pei Xiao
2024-10-23 8:00 ` Vlastimil Babka
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