diff options
| author | Dongli Zhang <dongli.zhang@oracle.com> | 2026-08-02 10:24:55 -0700 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2026-09-07 18:54:03 -0400 |
| commit | c952e607cb4aa3640e5ae07243d3f609dac94424 (patch) | |
| tree | f7cd1debe26c929a4a71460f85420d7ffee69cf3 /tools/perf/scripts/python/stackcollapse.py | |
| parent | 93fa09455fb1a9624b73d42ac1f83771f4818e80 (diff) | |
vhost-scsi: use kvzalloc for vq array allocation
vhost_scsi_open() allocates one "struct vhost_scsi_virtqueue" for each
virtqueue. With large max_io_vqs values, this array can require a
high-order contiguous allocation and trigger a page allocator warning.
hv# cat /sys/module/vhost_scsi/parameters/max_io_vqs
256
[ 766.075787] ------------[ cut here ]------------
[ 766.077030] WARNING: mm/page_alloc.c:5280 at __alloc_frozen_pages_noprof+0x32c/0x15c0, CPU#23: qemu-system-x86/5964
... ...
[ 766.080351] RIP: 0010:__alloc_frozen_pages_noprof+0x32c/0x15c0
... ...
[ 766.085813] Call Trace:
[ 766.085969] <TASK>
[ 766.086098] ? srso_alias_return_thunk+0x5/0xfbef5
[ 766.086365] ? context_struct_compute_av+0x38a/0x4b0
[ 766.086652] alloc_pages_mpol+0x9f/0x170
[ 766.086883] ___kmalloc_large_node+0xb6/0xd0
[ 766.087124] ? srso_alias_return_thunk+0x5/0xfbef5
[ 766.087389] __kmalloc_large_node_noprof+0x18/0xa0
[ 766.087655] __kmalloc_noprof+0x3a0/0x440
[ 766.087877] ? vhost_scsi_open+0xcb/0x2d0 [vhost_scsi]
[ 766.088162] vhost_scsi_open+0xcb/0x2d0 [vhost_scsi]
[ 766.088449] misc_open+0x123/0x160
[ 766.088679] chrdev_open+0xb1/0x230
[ 766.088885] ? __pfx_chrdev_open+0x10/0x10
[ 766.089157] do_dentry_open+0x11a/0x470
[ 766.089389] vfs_open+0x29/0xf0
[ 766.089596] path_openat+0x7c0/0x1100
[ 766.089821] do_file_open+0xdd/0x190
[ 766.090032] ? srso_alias_return_thunk+0x5/0xfbef5
[ 766.090332] do_sys_openat2+0x7e/0x100
[ 766.090601] __x64_sys_openat+0x51/0xa0
[ 766.090857] do_syscall_64+0xfe/0x590
[ 766.091087] entry_SYSCALL_64_after_hwframe+0x77/0x7f
[ 766.091411] RIP: 0033:0x7f9525a11fa6
The array does not require physical contiguity, so allocate it with
kvzalloc_objs() and free it with kvfree().
Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-ID: <20260802172534.260047-2-dongli.zhang@oracle.com>
Diffstat (limited to 'tools/perf/scripts/python/stackcollapse.py')
0 files changed, 0 insertions, 0 deletions