The size of 'struct vhost_scsi' is order-10 (~2.3MB). It may take long time
delay by kzalloc() to compact memory pages by retrying multiple times when
there is a lack of high-order pages. As a result, there is latency to
create a VM (with vhost-scsi) or to hotadd vhost-scsi-based storage.
The prior commit 595cb754983d ("vhost/scsi: use vmalloc for order-10
allocation") prefers to fallback only when really needed, while this patch
allocates with kvzalloc() with __GFP_NORETRY implicitly set to avoid
retrying memory pages compact for multiple times.
The __GFP_NORETRY is implicitly set if the size to allocate is more than
PAGE_SZIE and when __GFP_RETRY_MAYFAIL is not explicitly set.
Cc: Aruna Ramakrishna <[email protected]>
Cc: Joe Jin <[email protected]>
Signed-off-by: Dongli Zhang <[email protected]>
---
Changed since v1:
- To combine kzalloc() and vzalloc() as kvzalloc()
(suggested by Jason Wang)
drivers/vhost/scsi.c | 9 +++------
1 file changed, 3 insertions(+), 6 deletions(-)
diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
index 4ce9f00ae10e..5de21ad4bd05 100644
--- a/drivers/vhost/scsi.c
+++ b/drivers/vhost/scsi.c
@@ -1814,12 +1814,9 @@ static int vhost_scsi_open(struct inode *inode, struct file *f)
struct vhost_virtqueue **vqs;
int r = -ENOMEM, i;
- vs = kzalloc(sizeof(*vs), GFP_KERNEL | __GFP_NOWARN | __GFP_RETRY_MAYFAIL);
- if (!vs) {
- vs = vzalloc(sizeof(*vs));
- if (!vs)
- goto err_vs;
- }
+ vs = kvzalloc(sizeof(*vs), GFP_KERNEL);
+ if (!vs)
+ goto err_vs;
vqs = kmalloc_array(VHOST_SCSI_MAX_VQ, sizeof(*vqs), GFP_KERNEL);
if (!vqs)
--
2.17.1
According to my "git send-email" history, I have CCed [email protected]. Not
sure why Jason is not on the list.
CCed Jason. Thank you very much!
Dongli Zhang
On 1/23/21 12:08 AM, Dongli Zhang wrote:
> The size of 'struct vhost_scsi' is order-10 (~2.3MB). It may take long time
> delay by kzalloc() to compact memory pages by retrying multiple times when
> there is a lack of high-order pages. As a result, there is latency to
> create a VM (with vhost-scsi) or to hotadd vhost-scsi-based storage.
>
> The prior commit 595cb754983d ("vhost/scsi: use vmalloc for order-10
> allocation") prefers to fallback only when really needed, while this patch
> allocates with kvzalloc() with __GFP_NORETRY implicitly set to avoid
> retrying memory pages compact for multiple times.
>
> The __GFP_NORETRY is implicitly set if the size to allocate is more than
> PAGE_SZIE and when __GFP_RETRY_MAYFAIL is not explicitly set.
>
> Cc: Aruna Ramakrishna <[email protected]>
> Cc: Joe Jin <[email protected]>
> Signed-off-by: Dongli Zhang <[email protected]>
> ---
> Changed since v1:
> - To combine kzalloc() and vzalloc() as kvzalloc()
> (suggested by Jason Wang)
>
> drivers/vhost/scsi.c | 9 +++------
> 1 file changed, 3 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
> index 4ce9f00ae10e..5de21ad4bd05 100644
> --- a/drivers/vhost/scsi.c
> +++ b/drivers/vhost/scsi.c
> @@ -1814,12 +1814,9 @@ static int vhost_scsi_open(struct inode *inode, struct file *f)
> struct vhost_virtqueue **vqs;
> int r = -ENOMEM, i;
>
> - vs = kzalloc(sizeof(*vs), GFP_KERNEL | __GFP_NOWARN | __GFP_RETRY_MAYFAIL);
> - if (!vs) {
> - vs = vzalloc(sizeof(*vs));
> - if (!vs)
> - goto err_vs;
> - }
> + vs = kvzalloc(sizeof(*vs), GFP_KERNEL);
> + if (!vs)
> + goto err_vs;
>
> vqs = kmalloc_array(VHOST_SCSI_MAX_VQ, sizeof(*vqs), GFP_KERNEL);
> if (!vqs)
>
On 2021/1/23 下午4:08, Dongli Zhang wrote:
> The size of 'struct vhost_scsi' is order-10 (~2.3MB). It may take long time
> delay by kzalloc() to compact memory pages by retrying multiple times when
> there is a lack of high-order pages. As a result, there is latency to
> create a VM (with vhost-scsi) or to hotadd vhost-scsi-based storage.
>
> The prior commit 595cb754983d ("vhost/scsi: use vmalloc for order-10
> allocation") prefers to fallback only when really needed, while this patch
> allocates with kvzalloc() with __GFP_NORETRY implicitly set to avoid
> retrying memory pages compact for multiple times.
>
> The __GFP_NORETRY is implicitly set if the size to allocate is more than
> PAGE_SZIE and when __GFP_RETRY_MAYFAIL is not explicitly set.
>
> Cc: Aruna Ramakrishna <[email protected]>
> Cc: Joe Jin <[email protected]>
> Signed-off-by: Dongli Zhang <[email protected]>
> ---
> Changed since v1:
> - To combine kzalloc() and vzalloc() as kvzalloc()
> (suggested by Jason Wang)
>
> drivers/vhost/scsi.c | 9 +++------
> 1 file changed, 3 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
> index 4ce9f00ae10e..5de21ad4bd05 100644
> --- a/drivers/vhost/scsi.c
> +++ b/drivers/vhost/scsi.c
> @@ -1814,12 +1814,9 @@ static int vhost_scsi_open(struct inode *inode, struct file *f)
> struct vhost_virtqueue **vqs;
> int r = -ENOMEM, i;
>
> - vs = kzalloc(sizeof(*vs), GFP_KERNEL | __GFP_NOWARN | __GFP_RETRY_MAYFAIL);
> - if (!vs) {
> - vs = vzalloc(sizeof(*vs));
> - if (!vs)
> - goto err_vs;
> - }
> + vs = kvzalloc(sizeof(*vs), GFP_KERNEL);
> + if (!vs)
> + goto err_vs;
>
> vqs = kmalloc_array(VHOST_SCSI_MAX_VQ, sizeof(*vqs), GFP_KERNEL);
> if (!vqs)
Acked-by: Jason Wang <[email protected]>
Can anyone help to review this patch and give a review-by for it please?
Thanks,
Joe
On 1/24/21 7:12 PM, Jason Wang wrote:
>
> On 2021/1/23 下午4:08, Dongli Zhang wrote:
>> The size of 'struct vhost_scsi' is order-10 (~2.3MB). It may take long time
>> delay by kzalloc() to compact memory pages by retrying multiple times when
>> there is a lack of high-order pages. As a result, there is latency to
>> create a VM (with vhost-scsi) or to hotadd vhost-scsi-based storage.
>>
>> The prior commit 595cb754983d ("vhost/scsi: use vmalloc for order-10
>> allocation") prefers to fallback only when really needed, while this patch
>> allocates with kvzalloc() with __GFP_NORETRY implicitly set to avoid
>> retrying memory pages compact for multiple times.
>>
>> The __GFP_NORETRY is implicitly set if the size to allocate is more than
>> PAGE_SZIE and when __GFP_RETRY_MAYFAIL is not explicitly set.
>>
>> Cc: Aruna Ramakrishna <[email protected]>
>> Cc: Joe Jin <[email protected]>
>> Signed-off-by: Dongli Zhang <[email protected]>
>> ---
>> Changed since v1:
>> - To combine kzalloc() and vzalloc() as kvzalloc()
>> (suggested by Jason Wang)
>>
>> drivers/vhost/scsi.c | 9 +++------
>> 1 file changed, 3 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
>> index 4ce9f00ae10e..5de21ad4bd05 100644
>> --- a/drivers/vhost/scsi.c
>> +++ b/drivers/vhost/scsi.c
>> @@ -1814,12 +1814,9 @@ static int vhost_scsi_open(struct inode *inode, struct file *f)
>> struct vhost_virtqueue **vqs;
>> int r = -ENOMEM, i;
>> - vs = kzalloc(sizeof(*vs), GFP_KERNEL | __GFP_NOWARN | __GFP_RETRY_MAYFAIL);
>> - if (!vs) {
>> - vs = vzalloc(sizeof(*vs));
>> - if (!vs)
>> - goto err_vs;
>> - }
>> + vs = kvzalloc(sizeof(*vs), GFP_KERNEL);
>> + if (!vs)
>> + goto err_vs;
>> vqs = kmalloc_array(VHOST_SCSI_MAX_VQ, sizeof(*vqs), GFP_KERNEL);
>> if (!vqs)
>
>
> Acked-by: Jason Wang <[email protected]>
>
>
>
> The size of 'struct vhost_scsi' is order-10 (~2.3MB). It may take long time
> delay by kzalloc() to compact memory pages by retrying multiple times when
> there is a lack of high-order pages. As a result, there is latency to
> create a VM (with vhost-scsi) or to hotadd vhost-scsi-based storage.
>
> The prior commit 595cb754983d ("vhost/scsi: use vmalloc for order-10
> allocation") prefers to fallback only when really needed, while this patch
> allocates with kvzalloc() with __GFP_NORETRY implicitly set to avoid
> retrying memory pages compact for multiple times.
>
> The __GFP_NORETRY is implicitly set if the size to allocate is more than
> PAGE_SZIE and when __GFP_RETRY_MAYFAIL is not explicitly set.
>
> Cc: Aruna Ramakrishna <[email protected]>
> Cc: Joe Jin <[email protected]>
> Signed-off-by: Dongli Zhang <[email protected]>
> ---
> Changed since v1:
> - To combine kzalloc() and vzalloc() as kvzalloc()
> (suggested by Jason Wang)
>
> drivers/vhost/scsi.c | 9 +++------
> 1 file changed, 3 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
> index 4ce9f00ae10e..5de21ad4bd05 100644
> --- a/drivers/vhost/scsi.c
> +++ b/drivers/vhost/scsi.c
> @@ -1814,12 +1814,9 @@ static int vhost_scsi_open(struct inode *inode, struct file *f)
> struct vhost_virtqueue **vqs;
> int r = -ENOMEM, i;
>
> - vs = kzalloc(sizeof(*vs), GFP_KERNEL | __GFP_NOWARN | __GFP_RETRY_MAYFAIL);
> - if (!vs) {
> - vs = vzalloc(sizeof(*vs));
> - if (!vs)
> - goto err_vs;
> - }
> + vs = kvzalloc(sizeof(*vs), GFP_KERNEL);
> + if (!vs)
> + goto err_vs;
>
> vqs = kmalloc_array(VHOST_SCSI_MAX_VQ, sizeof(*vqs), GFP_KERNEL);
> if (!vqs)
Acked-by: Pankaj Gupta <[email protected]>
Greeting,
FYI, we noticed the following commit (built with gcc-9):
commit: 79991caf5202c7989928be534727805f8f68bb8d ("vdpa_sim_net: Add support for user supported devices")
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git Dongli-Zhang/vhost-scsi-alloc-vhost_scsi-with-kvzalloc-to-avoid-delay/20210129-191605
in testcase: trinity
version: trinity-static-x86_64-x86_64-f93256fb_2019-08-28
with following parameters:
runtime: 300s
test-description: Trinity is a linux system call fuzz tester.
test-url: http://codemonkey.org.uk/projects/trinity/
on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 8G
caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):
+-------------------------------------------------------------------------+------------+------------+
| | 39502d042a | 79991caf52 |
+-------------------------------------------------------------------------+------------+------------+
| boot_successes | 0 | 0 |
| boot_failures | 62 | 57 |
| WARNING:suspicious_RCU_usage | 62 | 57 |
| security/smack/smack_lsm.c:#RCU-list_traversed_in_non-reader_section | 62 | 57 |
| security/smack/smack_access.c:#RCU-list_traversed_in_non-reader_section | 62 | 57 |
| BUG:workqueue_lockup-pool | 33 | 40 |
| BUG:kernel_hang_in_boot_stage | 6 | 2 |
| net/mac80211/util.c:#RCU-list_traversed_in_non-reader_section | 23 | 15 |
| WARNING:SOFTIRQ-safe->SOFTIRQ-unsafe_lock_order_detected | 18 | |
| WARNING:inconsistent_lock_state | 5 | |
| inconsistent{SOFTIRQ-ON-W}->{IN-SOFTIRQ-W}usage | 5 | |
| calltrace:asm_call_irq_on_stack | 2 | |
| RIP:lock_acquire | 2 | |
| RIP:check_kcov_mode | 1 | |
| RIP:native_safe_halt | 2 | |
| INFO:rcu_sched_self-detected_stall_on_CPU | 2 | |
| RIP:clear_page_rep | 1 | |
| WARNING:at_drivers/gpu/drm/vkms/vkms_crtc.c:#vkms_vblank_simulate | 9 | 7 |
| RIP:vkms_vblank_simulate | 9 | 7 |
| RIP:__slab_alloc | 3 | 3 |
| RIP:__do_softirq | 2 | |
| RIP:console_unlock | 6 | 3 |
| invoked_oom-killer:gfp_mask=0x | 1 | |
| Mem-Info | 1 | |
| RIP:vprintk_emit | 1 | |
| RIP:__asan_load4 | 1 | |
| kernel_BUG_at_kernel/sched/core.c | 0 | 1 |
| invalid_opcode:#[##] | 0 | 1 |
| RIP:sched_cpu_dying | 0 | 1 |
| WARNING:possible_circular_locking_dependency_detected | 0 | 1 |
| Kernel_panic-not_syncing:Fatal_exception | 0 | 1 |
| net/ipv4/ipmr.c:#RCU-list_traversed_in_non-reader_section | 0 | 8 |
| RIP:arch_local_irq_restore | 0 | 1 |
| RIP:idr_get_free | 0 | 1 |
| net/ipv6/ip6mr.c:#RCU-list_traversed_in_non-reader_section | 0 | 2 |
+-------------------------------------------------------------------------+------------+------------+
If you fix the issue, kindly add following tag
Reported-by: kernel test robot <[email protected]>
[ 890.196279] =============================
[ 890.212608] WARNING: suspicious RCU usage
[ 890.228281] 5.11.0-rc4-00008-g79991caf5202 #1 Tainted: G W
[ 890.244087] -----------------------------
[ 890.259417] net/ipv4/ipmr.c:138 RCU-list traversed in non-reader section!!
[ 890.275043]
[ 890.275043] other info that might help us debug this:
[ 890.275043]
[ 890.318497]
[ 890.318497] rcu_scheduler_active = 2, debug_locks = 1
[ 890.346089] 2 locks held by trinity-c1/2476:
[ 890.360897] #0: ffff888149d6f400 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xc0/0xe0
[ 890.375165] #1: ffff8881cabfd5c8 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xa0/0x9c0
[ 890.389706]
[ 890.389706] stack backtrace:
[ 890.416375] CPU: 1 PID: 2476 Comm: trinity-c1 Tainted: G W 5.11.0-rc4-00008-g79991caf5202 #1
[ 890.430706] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
[ 890.444971] Call Trace:
[ 890.458554] dump_stack+0x15f/0x1bf
[ 890.471996] ipmr_get_table+0x140/0x160
[ 890.485328] ipmr_vif_seq_start+0x4d/0xe0
[ 890.498620] seq_read_iter+0x1b2/0x9c0
[ 890.511469] ? kvm_sched_clock_read+0x14/0x40
[ 890.524008] ? sched_clock+0x1b/0x40
[ 890.536095] ? iov_iter_init+0x7c/0xa0
[ 890.548028] seq_read+0x2fd/0x3e0
[ 890.559948] ? seq_hlist_next_percpu+0x140/0x140
[ 890.572204] ? should_fail+0x78/0x2a0
[ 890.584189] ? write_comp_data+0x2a/0xa0
[ 890.596235] ? __sanitizer_cov_trace_pc+0x1d/0x60
[ 890.608134] ? seq_hlist_next_percpu+0x140/0x140
[ 890.620042] proc_reg_read+0x14e/0x180
[ 890.631585] do_iter_read+0x397/0x420
[ 890.642843] vfs_readv+0xf5/0x160
[ 890.653833] ? vfs_iter_read+0x80/0x80
[ 890.664229] ? __fdget_pos+0xc0/0xe0
[ 890.674236] ? pvclock_clocksource_read+0xd9/0x1a0
[ 890.684259] ? kvm_sched_clock_read+0x14/0x40
[ 890.693852] ? sched_clock+0x1b/0x40
[ 890.702898] ? sched_clock_cpu+0x18/0x120
[ 890.711648] ? write_comp_data+0x2a/0xa0
[ 890.720243] ? __sanitizer_cov_trace_pc+0x1d/0x60
[ 890.729290] do_readv+0x111/0x260
[ 890.738205] ? vfs_readv+0x160/0x160
[ 890.747154] ? lockdep_hardirqs_on+0x77/0x100
[ 890.756100] ? syscall_enter_from_user_mode+0x8a/0x100
[ 890.765126] do_syscall_64+0x34/0x80
[ 890.773795] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 890.782630] RIP: 0033:0x453b29
[ 890.791189] Code: 00 f3 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b 84 00 00 c3 66 2e 0f 1f 84 00 00 00 00
[ 890.810866] RSP: 002b:00007ffcda44fb18 EFLAGS: 00000246 ORIG_RAX: 0000000000000013
[ 890.820764] RAX: ffffffffffffffda RBX: 0000000000000013 RCX: 0000000000453b29
[ 890.830792] RDX: 000000000000009a RSI: 0000000001de1c00 RDI: 00000000000000b9
[ 890.840626] RBP: 00007ffcda44fbc0 R08: 722c279d69ffc468 R09: 0000000000000400
[ 890.850366] R10: 0098d82a42c63c22 R11: 0000000000000246 R12: 0000000000000002
[ 890.860001] R13: 00007f042ae6f058 R14: 00000000010a2830 R15: 00007f042ae6f000
To reproduce:
# build kernel
cd linux
cp config-5.11.0-rc4-00008-g79991caf5202 .config
make HOSTCC=gcc-9 CC=gcc-9 ARCH=x86_64 olddefconfig prepare modules_prepare bzImage
git clone https://github.com/intel/lkp-tests.git
cd lkp-tests
bin/lkp qemu -k <bzImage> job-script # job-script is attached in this email
Thanks,
Oliver Sang
Is it possible that the issue is not due to this change?
This change is just to call different API to allocate memory, which is
equivalent to kzalloc()+vzalloc().
Before the change:
try kzalloc(sizeof(*vs), GFP_KERNEL | __GFP_NOWARN | __GFP_RETRY_MAYFAIL);
... and then below if the former is failed.
vzalloc(sizeof(*vs));
After the change:
try kmalloc_node(size, FP_KERNEL|GFP_ZERO|__GFP_NOWARN|__GFP_NORETRY, node);
... and then below if the former is failed
__vmalloc_node(size, 1, GFP_KERNEL|GFP_ZERO, node, __builtin_return_address(0));
The below is the first WARNING in uploaded dmesg. I assume it was called before
to open /dev/vhost-scsi.
Will this test try to open /dev/vhost-scsi?
[ 5.095515] =============================
[ 5.095515] WARNING: suspicious RCU usage
[ 5.095515] 5.11.0-rc4-00008-g79991caf5202 #1 Not tainted
[ 5.095534] -----------------------------
[ 5.096041] security/smack/smack_lsm.c:351 RCU-list traversed in non-reader
section!!
[ 5.096982]
[ 5.096982] other info that might help us debug this:
[ 5.096982]
[ 5.097953]
[ 5.097953] rcu_scheduler_active = 1, debug_locks = 1
[ 5.098739] no locks held by kthreadd/2.
[ 5.099237]
[ 5.099237] stack backtrace:
[ 5.099537] CPU: 0 PID: 2 Comm: kthreadd Not tainted
5.11.0-rc4-00008-g79991caf5202 #1
[ 5.100470] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.12.0-1 04/01/2014
[ 5.101442] Call Trace:
[ 5.101807] dump_stack+0x15f/0x1bf
[ 5.102298] smack_cred_prepare+0x400/0x420
[ 5.102840] ? security_prepare_creds+0xd4/0x120
[ 5.103441] security_prepare_creds+0x84/0x120
[ 5.103515] prepare_creds+0x3f1/0x580
[ 5.103515] copy_creds+0x65/0x480
[ 5.103515] copy_process+0x7b4/0x3600
[ 5.103515] ? check_prev_add+0xa40/0xa40
[ 5.103515] ? lockdep_enabled+0xd/0x60
[ 5.103515] ? lock_is_held_type+0x1a/0x100
[ 5.103515] ? __cleanup_sighand+0xc0/0xc0
[ 5.103515] ? lockdep_unlock+0x39/0x160
[ 5.103515] kernel_clone+0x165/0xd20
[ 5.103515] ? copy_init_mm+0x20/0x20
[ 5.103515] ? pvclock_clocksource_read+0xd9/0x1a0
[ 5.103515] ? sched_clock_local+0x99/0xc0
[ 5.103515] ? kthread_insert_work_sanity_check+0xc0/0xc0
[ 5.103515] kernel_thread+0xba/0x100
[ 5.103515] ? __ia32_sys_clone3+0x40/0x40
[ 5.103515] ? kthread_insert_work_sanity_check+0xc0/0xc0
[ 5.103515] ? do_raw_spin_unlock+0xa9/0x160
[ 5.103515] kthreadd+0x68f/0x7a0
[ 5.103515] ? kthread_create_on_cpu+0x160/0x160
[ 5.103515] ? lockdep_hardirqs_on+0x77/0x100
[ 5.103515] ? _raw_spin_unlock_irq+0x24/0x60
[ 5.103515] ? kthread_create_on_cpu+0x160/0x160
[ 5.103515] ret_from_fork+0x22/0x30
Thank you very much!
Dongli Zhang
On 2/6/21 7:03 PM, kernel test robot wrote:
>
> Greeting,
>
> FYI, we noticed the following commit (built with gcc-9):
>
> commit: 79991caf5202c7989928be534727805f8f68bb8d ("vdpa_sim_net: Add support for user supported devices")
> https://urldefense.com/v3/__https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git__;!!GqivPVa7Brio!LfgrgVVtPAjwjqTZX8yANgsix4f3cJmAA_CcMeCVymh5XYcamWdR9dnbIQA-p61PJtI$ Dongli-Zhang/vhost-scsi-alloc-vhost_scsi-with-kvzalloc-to-avoid-delay/20210129-191605
>
>
> in testcase: trinity
> version: trinity-static-x86_64-x86_64-f93256fb_2019-08-28
> with following parameters:
>
> runtime: 300s
>
> test-description: Trinity is a linux system call fuzz tester.
> test-url: https://urldefense.com/v3/__http://codemonkey.org.uk/projects/trinity/__;!!GqivPVa7Brio!LfgrgVVtPAjwjqTZX8yANgsix4f3cJmAA_CcMeCVymh5XYcamWdR9dnbIQA-6Y4x88c$
>
>
> on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 8G
>
> caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):
>
>
> +-------------------------------------------------------------------------+------------+------------+
> | | 39502d042a | 79991caf52 |
> +-------------------------------------------------------------------------+------------+------------+
> | boot_successes | 0 | 0 |
> | boot_failures | 62 | 57 |
> | WARNING:suspicious_RCU_usage | 62 | 57 |
> | security/smack/smack_lsm.c:#RCU-list_traversed_in_non-reader_section | 62 | 57 |
> | security/smack/smack_access.c:#RCU-list_traversed_in_non-reader_section | 62 | 57 |
> | BUG:workqueue_lockup-pool | 33 | 40 |
> | BUG:kernel_hang_in_boot_stage | 6 | 2 |
> | net/mac80211/util.c:#RCU-list_traversed_in_non-reader_section | 23 | 15 |
> | WARNING:SOFTIRQ-safe->SOFTIRQ-unsafe_lock_order_detected | 18 | |
> | WARNING:inconsistent_lock_state | 5 | |
> | inconsistent{SOFTIRQ-ON-W}->{IN-SOFTIRQ-W}usage | 5 | |
> | calltrace:asm_call_irq_on_stack | 2 | |
> | RIP:lock_acquire | 2 | |
> | RIP:check_kcov_mode | 1 | |
> | RIP:native_safe_halt | 2 | |
> | INFO:rcu_sched_self-detected_stall_on_CPU | 2 | |
> | RIP:clear_page_rep | 1 | |
> | WARNING:at_drivers/gpu/drm/vkms/vkms_crtc.c:#vkms_vblank_simulate | 9 | 7 |
> | RIP:vkms_vblank_simulate | 9 | 7 |
> | RIP:__slab_alloc | 3 | 3 |
> | RIP:__do_softirq | 2 | |
> | RIP:console_unlock | 6 | 3 |
> | invoked_oom-killer:gfp_mask=0x | 1 | |
> | Mem-Info | 1 | |
> | RIP:vprintk_emit | 1 | |
> | RIP:__asan_load4 | 1 | |
> | kernel_BUG_at_kernel/sched/core.c | 0 | 1 |
> | invalid_opcode:#[##] | 0 | 1 |
> | RIP:sched_cpu_dying | 0 | 1 |
> | WARNING:possible_circular_locking_dependency_detected | 0 | 1 |
> | Kernel_panic-not_syncing:Fatal_exception | 0 | 1 |
> | net/ipv4/ipmr.c:#RCU-list_traversed_in_non-reader_section | 0 | 8 |
> | RIP:arch_local_irq_restore | 0 | 1 |
> | RIP:idr_get_free | 0 | 1 |
> | net/ipv6/ip6mr.c:#RCU-list_traversed_in_non-reader_section | 0 | 2 |
> +-------------------------------------------------------------------------+------------+------------+
>
>
> If you fix the issue, kindly add following tag
> Reported-by: kernel test robot <[email protected]>
>
>
> [ 890.196279] =============================
> [ 890.212608] WARNING: suspicious RCU usage
> [ 890.228281] 5.11.0-rc4-00008-g79991caf5202 #1 Tainted: G W
> [ 890.244087] -----------------------------
> [ 890.259417] net/ipv4/ipmr.c:138 RCU-list traversed in non-reader section!!
> [ 890.275043]
> [ 890.275043] other info that might help us debug this:
> [ 890.275043]
> [ 890.318497]
> [ 890.318497] rcu_scheduler_active = 2, debug_locks = 1
> [ 890.346089] 2 locks held by trinity-c1/2476:
> [ 890.360897] #0: ffff888149d6f400 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xc0/0xe0
> [ 890.375165] #1: ffff8881cabfd5c8 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xa0/0x9c0
> [ 890.389706]
> [ 890.389706] stack backtrace:
> [ 890.416375] CPU: 1 PID: 2476 Comm: trinity-c1 Tainted: G W 5.11.0-rc4-00008-g79991caf5202 #1
> [ 890.430706] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
> [ 890.444971] Call Trace:
> [ 890.458554] dump_stack+0x15f/0x1bf
> [ 890.471996] ipmr_get_table+0x140/0x160
> [ 890.485328] ipmr_vif_seq_start+0x4d/0xe0
> [ 890.498620] seq_read_iter+0x1b2/0x9c0
> [ 890.511469] ? kvm_sched_clock_read+0x14/0x40
> [ 890.524008] ? sched_clock+0x1b/0x40
> [ 890.536095] ? iov_iter_init+0x7c/0xa0
> [ 890.548028] seq_read+0x2fd/0x3e0
> [ 890.559948] ? seq_hlist_next_percpu+0x140/0x140
> [ 890.572204] ? should_fail+0x78/0x2a0
> [ 890.584189] ? write_comp_data+0x2a/0xa0
> [ 890.596235] ? __sanitizer_cov_trace_pc+0x1d/0x60
> [ 890.608134] ? seq_hlist_next_percpu+0x140/0x140
> [ 890.620042] proc_reg_read+0x14e/0x180
> [ 890.631585] do_iter_read+0x397/0x420
> [ 890.642843] vfs_readv+0xf5/0x160
> [ 890.653833] ? vfs_iter_read+0x80/0x80
> [ 890.664229] ? __fdget_pos+0xc0/0xe0
> [ 890.674236] ? pvclock_clocksource_read+0xd9/0x1a0
> [ 890.684259] ? kvm_sched_clock_read+0x14/0x40
> [ 890.693852] ? sched_clock+0x1b/0x40
> [ 890.702898] ? sched_clock_cpu+0x18/0x120
> [ 890.711648] ? write_comp_data+0x2a/0xa0
> [ 890.720243] ? __sanitizer_cov_trace_pc+0x1d/0x60
> [ 890.729290] do_readv+0x111/0x260
> [ 890.738205] ? vfs_readv+0x160/0x160
> [ 890.747154] ? lockdep_hardirqs_on+0x77/0x100
> [ 890.756100] ? syscall_enter_from_user_mode+0x8a/0x100
> [ 890.765126] do_syscall_64+0x34/0x80
> [ 890.773795] entry_SYSCALL_64_after_hwframe+0x44/0xa9
> [ 890.782630] RIP: 0033:0x453b29
> [ 890.791189] Code: 00 f3 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b 84 00 00 c3 66 2e 0f 1f 84 00 00 00 00
> [ 890.810866] RSP: 002b:00007ffcda44fb18 EFLAGS: 00000246 ORIG_RAX: 0000000000000013
> [ 890.820764] RAX: ffffffffffffffda RBX: 0000000000000013 RCX: 0000000000453b29
> [ 890.830792] RDX: 000000000000009a RSI: 0000000001de1c00 RDI: 00000000000000b9
> [ 890.840626] RBP: 00007ffcda44fbc0 R08: 722c279d69ffc468 R09: 0000000000000400
> [ 890.850366] R10: 0098d82a42c63c22 R11: 0000000000000246 R12: 0000000000000002
> [ 890.860001] R13: 00007f042ae6f058 R14: 00000000010a2830 R15: 00007f042ae6f000
>
>
>
> To reproduce:
>
> # build kernel
> cd linux
> cp config-5.11.0-rc4-00008-g79991caf5202 .config
> make HOSTCC=gcc-9 CC=gcc-9 ARCH=x86_64 olddefconfig prepare modules_prepare bzImage
>
> git clone https://urldefense.com/v3/__https://github.com/intel/lkp-tests.git__;!!GqivPVa7Brio!LfgrgVVtPAjwjqTZX8yANgsix4f3cJmAA_CcMeCVymh5XYcamWdR9dnbIQA-Qkr9TyI$
> cd lkp-tests
> bin/lkp qemu -k <bzImage> job-script # job-script is attached in this email
>
>
>
> Thanks,
> Oliver Sang
>
On Sun, Feb 07, 2021 at 11:03:30AM +0800, kernel test robot wrote:
>
> Greeting,
>
> FYI, we noticed the following commit (built with gcc-9):
>
> commit: 79991caf5202c7989928be534727805f8f68bb8d ("vdpa_sim_net: Add support for user supported devices")
> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git Dongli-Zhang/vhost-scsi-alloc-vhost_scsi-with-kvzalloc-to-avoid-delay/20210129-191605
>
>
> in testcase: trinity
> version: trinity-static-x86_64-x86_64-f93256fb_2019-08-28
> with following parameters:
>
> runtime: 300s
>
> test-description: Trinity is a linux system call fuzz tester.
> test-url: http://codemonkey.org.uk/projects/trinity/
>
>
> on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 8G
>
> caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):
>
Parav want to take a look?
--
MST
On 2/7/21 12:15 PM, Dongli Zhang wrote:
> Is it possible that the issue is not due to this change?
Looks this issue does not related your change, from dmesg output, when issue occurred, virtio was not loaded:
[ 502.508450] ------------[ cut here ]------------
[ 502.511859] WARNING: CPU: 0 PID: 1 at drivers/gpu/drm/vkms/vkms_crtc.c:21 vkms_vblank_simulate+0x22a/0x240
[ 502.524018] Modules linked in:
[ 502.539642] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.11.0-rc4-00008-g79991caf5202 #1
>
> This change is just to call different API to allocate memory, which is
> equivalent to kzalloc()+vzalloc().
>
> Before the change:
>
> try kzalloc(sizeof(*vs), GFP_KERNEL | __GFP_NOWARN | __GFP_RETRY_MAYFAIL);
>
> ... and then below if the former is failed.
>
> vzalloc(sizeof(*vs));
>
>
> After the change:
>
> try kmalloc_node(size, FP_KERNEL|GFP_ZERO|__GFP_NOWARN|__GFP_NORETRY, node);
>
> ... and then below if the former is failed
>
> __vmalloc_node(size, 1, GFP_KERNEL|GFP_ZERO, node, __builtin_return_address(0));
>
>
> The below is the first WARNING in uploaded dmesg. I assume it was called before
> to open /dev/vhost-scsi.
>
> Will this test try to open /dev/vhost-scsi?
>
> [ 5.095515] =============================
> [ 5.095515] WARNING: suspicious RCU usage
> [ 5.095515] 5.11.0-rc4-00008-g79991caf5202 #1 Not tainted
> [ 5.095534] -----------------------------
> [ 5.096041] security/smack/smack_lsm.c:351 RCU-list traversed in non-reader
> section!!
> [ 5.096982]
> [ 5.096982] other info that might help us debug this:
> [ 5.096982]
> [ 5.097953]
> [ 5.097953] rcu_scheduler_active = 1, debug_locks = 1
> [ 5.098739] no locks held by kthreadd/2.
> [ 5.099237]
> [ 5.099237] stack backtrace:
> [ 5.099537] CPU: 0 PID: 2 Comm: kthreadd Not tainted
> 5.11.0-rc4-00008-g79991caf5202 #1
> [ 5.100470] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
> 1.12.0-1 04/01/2014
> [ 5.101442] Call Trace:
> [ 5.101807] dump_stack+0x15f/0x1bf
> [ 5.102298] smack_cred_prepare+0x400/0x420
> [ 5.102840] ? security_prepare_creds+0xd4/0x120
> [ 5.103441] security_prepare_creds+0x84/0x120
> [ 5.103515] prepare_creds+0x3f1/0x580
> [ 5.103515] copy_creds+0x65/0x480
> [ 5.103515] copy_process+0x7b4/0x3600
> [ 5.103515] ? check_prev_add+0xa40/0xa40
> [ 5.103515] ? lockdep_enabled+0xd/0x60
> [ 5.103515] ? lock_is_held_type+0x1a/0x100
> [ 5.103515] ? __cleanup_sighand+0xc0/0xc0
> [ 5.103515] ? lockdep_unlock+0x39/0x160
> [ 5.103515] kernel_clone+0x165/0xd20
> [ 5.103515] ? copy_init_mm+0x20/0x20
> [ 5.103515] ? pvclock_clocksource_read+0xd9/0x1a0
> [ 5.103515] ? sched_clock_local+0x99/0xc0
> [ 5.103515] ? kthread_insert_work_sanity_check+0xc0/0xc0
> [ 5.103515] kernel_thread+0xba/0x100
> [ 5.103515] ? __ia32_sys_clone3+0x40/0x40
> [ 5.103515] ? kthread_insert_work_sanity_check+0xc0/0xc0
> [ 5.103515] ? do_raw_spin_unlock+0xa9/0x160
> [ 5.103515] kthreadd+0x68f/0x7a0
> [ 5.103515] ? kthread_create_on_cpu+0x160/0x160
> [ 5.103515] ? lockdep_hardirqs_on+0x77/0x100
> [ 5.103515] ? _raw_spin_unlock_irq+0x24/0x60
> [ 5.103515] ? kthread_create_on_cpu+0x160/0x160
> [ 5.103515] ret_from_fork+0x22/0x30
>
> Thank you very much!
>
> Dongli Zhang
>
>
> On 2/6/21 7:03 PM, kernel test robot wrote:
>> Greeting,
>>
>> FYI, we noticed the following commit (built with gcc-9):
>>
>> commit: 79991caf5202c7989928be534727805f8f68bb8d ("vdpa_sim_net: Add support for user supported devices")
>> https://urldefense.com/v3/__https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git__;!!GqivPVa7Brio!LfgrgVVtPAjwjqTZX8yANgsix4f3cJmAA_CcMeCVymh5XYcamWdR9dnbIQA-p61PJtI$ Dongli-Zhang/vhost-scsi-alloc-vhost_scsi-with-kvzalloc-to-avoid-delay/20210129-191605
>>
>>
>> in testcase: trinity
>> version: trinity-static-x86_64-x86_64-f93256fb_2019-08-28
>> with following parameters:
>>
>> runtime: 300s
>>
>> test-description: Trinity is a linux system call fuzz tester.
>> test-url: https://urldefense.com/v3/__http://codemonkey.org.uk/projects/trinity/__;!!GqivPVa7Brio!LfgrgVVtPAjwjqTZX8yANgsix4f3cJmAA_CcMeCVymh5XYcamWdR9dnbIQA-6Y4x88c$
>>
>>
>> on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 8G
>>
>> caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):
>>
>>
>> +-------------------------------------------------------------------------+------------+------------+
>> | | 39502d042a | 79991caf52 |
>> +-------------------------------------------------------------------------+------------+------------+
>> | boot_successes | 0 | 0 |
>> | boot_failures | 62 | 57 |
>> | WARNING:suspicious_RCU_usage | 62 | 57 |
>> | security/smack/smack_lsm.c:#RCU-list_traversed_in_non-reader_section | 62 | 57 |
>> | security/smack/smack_access.c:#RCU-list_traversed_in_non-reader_section | 62 | 57 |
>> | BUG:workqueue_lockup-pool | 33 | 40 |
>> | BUG:kernel_hang_in_boot_stage | 6 | 2 |
>> | net/mac80211/util.c:#RCU-list_traversed_in_non-reader_section | 23 | 15 |
>> | WARNING:SOFTIRQ-safe->SOFTIRQ-unsafe_lock_order_detected | 18 | |
>> | WARNING:inconsistent_lock_state | 5 | |
>> | inconsistent{SOFTIRQ-ON-W}->{IN-SOFTIRQ-W}usage | 5 | |
>> | calltrace:asm_call_irq_on_stack | 2 | |
>> | RIP:lock_acquire | 2 | |
>> | RIP:check_kcov_mode | 1 | |
>> | RIP:native_safe_halt | 2 | |
>> | INFO:rcu_sched_self-detected_stall_on_CPU | 2 | |
>> | RIP:clear_page_rep | 1 | |
>> | WARNING:at_drivers/gpu/drm/vkms/vkms_crtc.c:#vkms_vblank_simulate | 9 | 7 |
>> | RIP:vkms_vblank_simulate | 9 | 7 |
>> | RIP:__slab_alloc | 3 | 3 |
>> | RIP:__do_softirq | 2 | |
>> | RIP:console_unlock | 6 | 3 |
>> | invoked_oom-killer:gfp_mask=0x | 1 | |
>> | Mem-Info | 1 | |
>> | RIP:vprintk_emit | 1 | |
>> | RIP:__asan_load4 | 1 | |
>> | kernel_BUG_at_kernel/sched/core.c | 0 | 1 |
>> | invalid_opcode:#[##] | 0 | 1 |
>> | RIP:sched_cpu_dying | 0 | 1 |
>> | WARNING:possible_circular_locking_dependency_detected | 0 | 1 |
>> | Kernel_panic-not_syncing:Fatal_exception | 0 | 1 |
>> | net/ipv4/ipmr.c:#RCU-list_traversed_in_non-reader_section | 0 | 8 |
>> | RIP:arch_local_irq_restore | 0 | 1 |
>> | RIP:idr_get_free | 0 | 1 |
>> | net/ipv6/ip6mr.c:#RCU-list_traversed_in_non-reader_section | 0 | 2 |
>> +-------------------------------------------------------------------------+------------+------------+
>>
>>
>> If you fix the issue, kindly add following tag
>> Reported-by: kernel test robot <[email protected]>
>>
>>
>> [ 890.196279] =============================
>> [ 890.212608] WARNING: suspicious RCU usage
>> [ 890.228281] 5.11.0-rc4-00008-g79991caf5202 #1 Tainted: G W
>> [ 890.244087] -----------------------------
>> [ 890.259417] net/ipv4/ipmr.c:138 RCU-list traversed in non-reader section!!
>> [ 890.275043]
>> [ 890.275043] other info that might help us debug this:
>> [ 890.275043]
>> [ 890.318497]
>> [ 890.318497] rcu_scheduler_active = 2, debug_locks = 1
>> [ 890.346089] 2 locks held by trinity-c1/2476:
>> [ 890.360897] #0: ffff888149d6f400 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xc0/0xe0
>> [ 890.375165] #1: ffff8881cabfd5c8 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xa0/0x9c0
>> [ 890.389706]
>> [ 890.389706] stack backtrace:
>> [ 890.416375] CPU: 1 PID: 2476 Comm: trinity-c1 Tainted: G W 5.11.0-rc4-00008-g79991caf5202 #1
>> [ 890.430706] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
>> [ 890.444971] Call Trace:
>> [ 890.458554] dump_stack+0x15f/0x1bf
>> [ 890.471996] ipmr_get_table+0x140/0x160
>> [ 890.485328] ipmr_vif_seq_start+0x4d/0xe0
>> [ 890.498620] seq_read_iter+0x1b2/0x9c0
>> [ 890.511469] ? kvm_sched_clock_read+0x14/0x40
>> [ 890.524008] ? sched_clock+0x1b/0x40
>> [ 890.536095] ? iov_iter_init+0x7c/0xa0
>> [ 890.548028] seq_read+0x2fd/0x3e0
>> [ 890.559948] ? seq_hlist_next_percpu+0x140/0x140
>> [ 890.572204] ? should_fail+0x78/0x2a0
>> [ 890.584189] ? write_comp_data+0x2a/0xa0
>> [ 890.596235] ? __sanitizer_cov_trace_pc+0x1d/0x60
>> [ 890.608134] ? seq_hlist_next_percpu+0x140/0x140
>> [ 890.620042] proc_reg_read+0x14e/0x180
>> [ 890.631585] do_iter_read+0x397/0x420
>> [ 890.642843] vfs_readv+0xf5/0x160
>> [ 890.653833] ? vfs_iter_read+0x80/0x80
>> [ 890.664229] ? __fdget_pos+0xc0/0xe0
>> [ 890.674236] ? pvclock_clocksource_read+0xd9/0x1a0
>> [ 890.684259] ? kvm_sched_clock_read+0x14/0x40
>> [ 890.693852] ? sched_clock+0x1b/0x40
>> [ 890.702898] ? sched_clock_cpu+0x18/0x120
>> [ 890.711648] ? write_comp_data+0x2a/0xa0
>> [ 890.720243] ? __sanitizer_cov_trace_pc+0x1d/0x60
>> [ 890.729290] do_readv+0x111/0x260
>> [ 890.738205] ? vfs_readv+0x160/0x160
>> [ 890.747154] ? lockdep_hardirqs_on+0x77/0x100
>> [ 890.756100] ? syscall_enter_from_user_mode+0x8a/0x100
>> [ 890.765126] do_syscall_64+0x34/0x80
>> [ 890.773795] entry_SYSCALL_64_after_hwframe+0x44/0xa9
>> [ 890.782630] RIP: 0033:0x453b29
>> [ 890.791189] Code: 00 f3 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b 84 00 00 c3 66 2e 0f 1f 84 00 00 00 00
>> [ 890.810866] RSP: 002b:00007ffcda44fb18 EFLAGS: 00000246 ORIG_RAX: 0000000000000013
>> [ 890.820764] RAX: ffffffffffffffda RBX: 0000000000000013 RCX: 0000000000453b29
>> [ 890.830792] RDX: 000000000000009a RSI: 0000000001de1c00 RDI: 00000000000000b9
>> [ 890.840626] RBP: 00007ffcda44fbc0 R08: 722c279d69ffc468 R09: 0000000000000400
>> [ 890.850366] R10: 0098d82a42c63c22 R11: 0000000000000246 R12: 0000000000000002
>> [ 890.860001] R13: 00007f042ae6f058 R14: 00000000010a2830 R15: 00007f042ae6f000
>>
>>
>>
>> To reproduce:
>>
>> # build kernel
>> cd linux
>> cp config-5.11.0-rc4-00008-g79991caf5202 .config
>> make HOSTCC=gcc-9 CC=gcc-9 ARCH=x86_64 olddefconfig prepare modules_prepare bzImage
>>
>> git clone https://urldefense.com/v3/__https://github.com/intel/lkp-tests.git__;!!GqivPVa7Brio!LfgrgVVtPAjwjqTZX8yANgsix4f3cJmAA_CcMeCVymh5XYcamWdR9dnbIQA-Qkr9TyI$
>> cd lkp-tests
>> bin/lkp qemu -k <bzImage> job-script # job-script is attached in this email
>>
>>
>>
>> Thanks,
>> Oliver Sang
>>
Hi Joe and Dongli,
On Mon, Feb 08, 2021 at 08:10:21AM -0800, Joe Jin wrote:
> On 2/7/21 12:15 PM, Dongli Zhang wrote:
> > Is it possible that the issue is not due to this change?
>
> Looks this issue does not related your change, from dmesg output, when issue occurred, virtio was not loaded:
>
> [? 502.508450] ------------[ cut here ]------------
> [? 502.511859] WARNING: CPU: 0 PID: 1 at drivers/gpu/drm/vkms/vkms_crtc.c:21 vkms_vblank_simulate+0x22a/0x240
> [? 502.524018] Modules linked in:
> [? 502.539642] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.11.0-rc4-00008-g79991caf5202 #1
>
thanks for explanation and sorry for false positive.
we will investigate further to avoid such kind of false positive in the future.
> >
> > This change is just to call different API to allocate memory, which is
> > equivalent to kzalloc()+vzalloc().
> >
> > Before the change:
> >
> > try kzalloc(sizeof(*vs), GFP_KERNEL | __GFP_NOWARN | __GFP_RETRY_MAYFAIL);
> >
> > ... and then below if the former is failed.
> >
> > vzalloc(sizeof(*vs));
> >
> >
> > After the change:
> >
> > try kmalloc_node(size, FP_KERNEL|GFP_ZERO|__GFP_NOWARN|__GFP_NORETRY, node);
> >
> > ... and then below if the former is failed
> >
> > __vmalloc_node(size, 1, GFP_KERNEL|GFP_ZERO, node, __builtin_return_address(0));
> >
> >
> > The below is the first WARNING in uploaded dmesg. I assume it was called before
> > to open /dev/vhost-scsi.
> >
> > Will this test try to open /dev/vhost-scsi?
> >
> > [ 5.095515] =============================
> > [ 5.095515] WARNING: suspicious RCU usage
> > [ 5.095515] 5.11.0-rc4-00008-g79991caf5202 #1 Not tainted
> > [ 5.095534] -----------------------------
> > [ 5.096041] security/smack/smack_lsm.c:351 RCU-list traversed in non-reader
> > section!!
> > [ 5.096982]
> > [ 5.096982] other info that might help us debug this:
> > [ 5.096982]
> > [ 5.097953]
> > [ 5.097953] rcu_scheduler_active = 1, debug_locks = 1
> > [ 5.098739] no locks held by kthreadd/2.
> > [ 5.099237]
> > [ 5.099237] stack backtrace:
> > [ 5.099537] CPU: 0 PID: 2 Comm: kthreadd Not tainted
> > 5.11.0-rc4-00008-g79991caf5202 #1
> > [ 5.100470] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
> > 1.12.0-1 04/01/2014
> > [ 5.101442] Call Trace:
> > [ 5.101807] dump_stack+0x15f/0x1bf
> > [ 5.102298] smack_cred_prepare+0x400/0x420
> > [ 5.102840] ? security_prepare_creds+0xd4/0x120
> > [ 5.103441] security_prepare_creds+0x84/0x120
> > [ 5.103515] prepare_creds+0x3f1/0x580
> > [ 5.103515] copy_creds+0x65/0x480
> > [ 5.103515] copy_process+0x7b4/0x3600
> > [ 5.103515] ? check_prev_add+0xa40/0xa40
> > [ 5.103515] ? lockdep_enabled+0xd/0x60
> > [ 5.103515] ? lock_is_held_type+0x1a/0x100
> > [ 5.103515] ? __cleanup_sighand+0xc0/0xc0
> > [ 5.103515] ? lockdep_unlock+0x39/0x160
> > [ 5.103515] kernel_clone+0x165/0xd20
> > [ 5.103515] ? copy_init_mm+0x20/0x20
> > [ 5.103515] ? pvclock_clocksource_read+0xd9/0x1a0
> > [ 5.103515] ? sched_clock_local+0x99/0xc0
> > [ 5.103515] ? kthread_insert_work_sanity_check+0xc0/0xc0
> > [ 5.103515] kernel_thread+0xba/0x100
> > [ 5.103515] ? __ia32_sys_clone3+0x40/0x40
> > [ 5.103515] ? kthread_insert_work_sanity_check+0xc0/0xc0
> > [ 5.103515] ? do_raw_spin_unlock+0xa9/0x160
> > [ 5.103515] kthreadd+0x68f/0x7a0
> > [ 5.103515] ? kthread_create_on_cpu+0x160/0x160
> > [ 5.103515] ? lockdep_hardirqs_on+0x77/0x100
> > [ 5.103515] ? _raw_spin_unlock_irq+0x24/0x60
> > [ 5.103515] ? kthread_create_on_cpu+0x160/0x160
> > [ 5.103515] ret_from_fork+0x22/0x30
> >
> > Thank you very much!
> >
> > Dongli Zhang
> >
> >
> > On 2/6/21 7:03 PM, kernel test robot wrote:
> >> Greeting,
> >>
> >> FYI, we noticed the following commit (built with gcc-9):
> >>
> >> commit: 79991caf5202c7989928be534727805f8f68bb8d ("vdpa_sim_net: Add support for user supported devices")
> >> https://urldefense.com/v3/__https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git__;!!GqivPVa7Brio!LfgrgVVtPAjwjqTZX8yANgsix4f3cJmAA_CcMeCVymh5XYcamWdR9dnbIQA-p61PJtI$ Dongli-Zhang/vhost-scsi-alloc-vhost_scsi-with-kvzalloc-to-avoid-delay/20210129-191605
> >>
> >>
> >> in testcase: trinity
> >> version: trinity-static-x86_64-x86_64-f93256fb_2019-08-28
> >> with following parameters:
> >>
> >> runtime: 300s
> >>
> >> test-description: Trinity is a linux system call fuzz tester.
> >> test-url: https://urldefense.com/v3/__http://codemonkey.org.uk/projects/trinity/__;!!GqivPVa7Brio!LfgrgVVtPAjwjqTZX8yANgsix4f3cJmAA_CcMeCVymh5XYcamWdR9dnbIQA-6Y4x88c$
> >>
> >>
> >> on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 8G
> >>
> >> caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):
> >>
> >>
> >> +-------------------------------------------------------------------------+------------+------------+
> >> | | 39502d042a | 79991caf52 |
> >> +-------------------------------------------------------------------------+------------+------------+
> >> | boot_successes | 0 | 0 |
> >> | boot_failures | 62 | 57 |
> >> | WARNING:suspicious_RCU_usage | 62 | 57 |
> >> | security/smack/smack_lsm.c:#RCU-list_traversed_in_non-reader_section | 62 | 57 |
> >> | security/smack/smack_access.c:#RCU-list_traversed_in_non-reader_section | 62 | 57 |
> >> | BUG:workqueue_lockup-pool | 33 | 40 |
> >> | BUG:kernel_hang_in_boot_stage | 6 | 2 |
> >> | net/mac80211/util.c:#RCU-list_traversed_in_non-reader_section | 23 | 15 |
> >> | WARNING:SOFTIRQ-safe->SOFTIRQ-unsafe_lock_order_detected | 18 | |
> >> | WARNING:inconsistent_lock_state | 5 | |
> >> | inconsistent{SOFTIRQ-ON-W}->{IN-SOFTIRQ-W}usage | 5 | |
> >> | calltrace:asm_call_irq_on_stack | 2 | |
> >> | RIP:lock_acquire | 2 | |
> >> | RIP:check_kcov_mode | 1 | |
> >> | RIP:native_safe_halt | 2 | |
> >> | INFO:rcu_sched_self-detected_stall_on_CPU | 2 | |
> >> | RIP:clear_page_rep | 1 | |
> >> | WARNING:at_drivers/gpu/drm/vkms/vkms_crtc.c:#vkms_vblank_simulate | 9 | 7 |
> >> | RIP:vkms_vblank_simulate | 9 | 7 |
> >> | RIP:__slab_alloc | 3 | 3 |
> >> | RIP:__do_softirq | 2 | |
> >> | RIP:console_unlock | 6 | 3 |
> >> | invoked_oom-killer:gfp_mask=0x | 1 | |
> >> | Mem-Info | 1 | |
> >> | RIP:vprintk_emit | 1 | |
> >> | RIP:__asan_load4 | 1 | |
> >> | kernel_BUG_at_kernel/sched/core.c | 0 | 1 |
> >> | invalid_opcode:#[##] | 0 | 1 |
> >> | RIP:sched_cpu_dying | 0 | 1 |
> >> | WARNING:possible_circular_locking_dependency_detected | 0 | 1 |
> >> | Kernel_panic-not_syncing:Fatal_exception | 0 | 1 |
> >> | net/ipv4/ipmr.c:#RCU-list_traversed_in_non-reader_section | 0 | 8 |
> >> | RIP:arch_local_irq_restore | 0 | 1 |
> >> | RIP:idr_get_free | 0 | 1 |
> >> | net/ipv6/ip6mr.c:#RCU-list_traversed_in_non-reader_section | 0 | 2 |
> >> +-------------------------------------------------------------------------+------------+------------+
> >>
> >>
> >> If you fix the issue, kindly add following tag
> >> Reported-by: kernel test robot <[email protected]>
> >>
> >>
> >> [ 890.196279] =============================
> >> [ 890.212608] WARNING: suspicious RCU usage
> >> [ 890.228281] 5.11.0-rc4-00008-g79991caf5202 #1 Tainted: G W
> >> [ 890.244087] -----------------------------
> >> [ 890.259417] net/ipv4/ipmr.c:138 RCU-list traversed in non-reader section!!
> >> [ 890.275043]
> >> [ 890.275043] other info that might help us debug this:
> >> [ 890.275043]
> >> [ 890.318497]
> >> [ 890.318497] rcu_scheduler_active = 2, debug_locks = 1
> >> [ 890.346089] 2 locks held by trinity-c1/2476:
> >> [ 890.360897] #0: ffff888149d6f400 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xc0/0xe0
> >> [ 890.375165] #1: ffff8881cabfd5c8 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xa0/0x9c0
> >> [ 890.389706]
> >> [ 890.389706] stack backtrace:
> >> [ 890.416375] CPU: 1 PID: 2476 Comm: trinity-c1 Tainted: G W 5.11.0-rc4-00008-g79991caf5202 #1
> >> [ 890.430706] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
> >> [ 890.444971] Call Trace:
> >> [ 890.458554] dump_stack+0x15f/0x1bf
> >> [ 890.471996] ipmr_get_table+0x140/0x160
> >> [ 890.485328] ipmr_vif_seq_start+0x4d/0xe0
> >> [ 890.498620] seq_read_iter+0x1b2/0x9c0
> >> [ 890.511469] ? kvm_sched_clock_read+0x14/0x40
> >> [ 890.524008] ? sched_clock+0x1b/0x40
> >> [ 890.536095] ? iov_iter_init+0x7c/0xa0
> >> [ 890.548028] seq_read+0x2fd/0x3e0
> >> [ 890.559948] ? seq_hlist_next_percpu+0x140/0x140
> >> [ 890.572204] ? should_fail+0x78/0x2a0
> >> [ 890.584189] ? write_comp_data+0x2a/0xa0
> >> [ 890.596235] ? __sanitizer_cov_trace_pc+0x1d/0x60
> >> [ 890.608134] ? seq_hlist_next_percpu+0x140/0x140
> >> [ 890.620042] proc_reg_read+0x14e/0x180
> >> [ 890.631585] do_iter_read+0x397/0x420
> >> [ 890.642843] vfs_readv+0xf5/0x160
> >> [ 890.653833] ? vfs_iter_read+0x80/0x80
> >> [ 890.664229] ? __fdget_pos+0xc0/0xe0
> >> [ 890.674236] ? pvclock_clocksource_read+0xd9/0x1a0
> >> [ 890.684259] ? kvm_sched_clock_read+0x14/0x40
> >> [ 890.693852] ? sched_clock+0x1b/0x40
> >> [ 890.702898] ? sched_clock_cpu+0x18/0x120
> >> [ 890.711648] ? write_comp_data+0x2a/0xa0
> >> [ 890.720243] ? __sanitizer_cov_trace_pc+0x1d/0x60
> >> [ 890.729290] do_readv+0x111/0x260
> >> [ 890.738205] ? vfs_readv+0x160/0x160
> >> [ 890.747154] ? lockdep_hardirqs_on+0x77/0x100
> >> [ 890.756100] ? syscall_enter_from_user_mode+0x8a/0x100
> >> [ 890.765126] do_syscall_64+0x34/0x80
> >> [ 890.773795] entry_SYSCALL_64_after_hwframe+0x44/0xa9
> >> [ 890.782630] RIP: 0033:0x453b29
> >> [ 890.791189] Code: 00 f3 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b 84 00 00 c3 66 2e 0f 1f 84 00 00 00 00
> >> [ 890.810866] RSP: 002b:00007ffcda44fb18 EFLAGS: 00000246 ORIG_RAX: 0000000000000013
> >> [ 890.820764] RAX: ffffffffffffffda RBX: 0000000000000013 RCX: 0000000000453b29
> >> [ 890.830792] RDX: 000000000000009a RSI: 0000000001de1c00 RDI: 00000000000000b9
> >> [ 890.840626] RBP: 00007ffcda44fbc0 R08: 722c279d69ffc468 R09: 0000000000000400
> >> [ 890.850366] R10: 0098d82a42c63c22 R11: 0000000000000246 R12: 0000000000000002
> >> [ 890.860001] R13: 00007f042ae6f058 R14: 00000000010a2830 R15: 00007f042ae6f000
> >>
> >>
> >>
> >> To reproduce:
> >>
> >> # build kernel
> >> cd linux
> >> cp config-5.11.0-rc4-00008-g79991caf5202 .config
> >> make HOSTCC=gcc-9 CC=gcc-9 ARCH=x86_64 olddefconfig prepare modules_prepare bzImage
> >>
> >> git clone https://urldefense.com/v3/__https://github.com/intel/lkp-tests.git__;!!GqivPVa7Brio!LfgrgVVtPAjwjqTZX8yANgsix4f3cJmAA_CcMeCVymh5XYcamWdR9dnbIQA-Qkr9TyI$
> >> cd lkp-tests
> >> bin/lkp qemu -k <bzImage> job-script # job-script is attached in this email
> >>
> >>
> >>
> >> Thanks,
> >> Oliver Sang
> >>
>