From 83cf4213bafc4e3c747f0a25ad22cfbf55af7e84 Mon Sep 17 00:00:00 2001 From: Taehee Yoo Date: Sat, 1 Feb 2020 16:43:39 +0000 Subject: [PATCH] netdevsim: use __GFP_NOWARN to avoid memalloc warning vfnum buffer size and binary_len buffer size is received by user-space. So, this buffer size could be too large. If so, kmalloc will internally print a warning message. This warning message is actually not necessary for the netdevsim module. So, this patch adds __GFP_NOWARN. Test commands: modprobe netdevsim echo 1 > /sys/bus/netdevsim/new_device echo 1000000000 > /sys/devices/netdevsim1/sriov_numvfs Splat looks like: [ 357.847266][ T1000] WARNING: CPU: 0 PID: 1000 at mm/page_alloc.c:4738 __alloc_pages_nodemask+0x2f3/0x740 [ 357.850273][ T1000] Modules linked in: netdevsim veth openvswitch nsh nf_conncount nf_nat nf_conntrack nf_defrx [ 357.852989][ T1000] CPU: 0 PID: 1000 Comm: bash Tainted: G B 5.5.0-rc5+ #270 [ 357.854334][ T1000] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 [ 357.855703][ T1000] RIP: 0010:__alloc_pages_nodemask+0x2f3/0x740 [ 357.856669][ T1000] Code: 64 fe ff ff 65 48 8b 04 25 c0 0f 02 00 48 05 f0 12 00 00 41 be 01 00 00 00 49 89 47 0 [ 357.860272][ T1000] RSP: 0018:ffff8880b7f47bd8 EFLAGS: 00010246 [ 357.861009][ T1000] RAX: ffffed1016fe8f80 RBX: 1ffff11016fe8fae RCX: 0000000000000000 [ 357.861843][ T1000] RDX: 0000000000000000 RSI: 0000000000000017 RDI: 0000000000000000 [ 357.862661][ T1000] RBP: 0000000000040dc0 R08: 1ffff11016fe8f67 R09: dffffc0000000000 [ 357.863509][ T1000] R10: ffff8880b7f47d68 R11: fffffbfff2798180 R12: 1ffff11016fe8f80 [ 357.864355][ T1000] R13: 0000000000000017 R14: 0000000000000017 R15: ffff8880c2038d68 [ 357.865178][ T1000] FS: 00007fd9a5b8c740(0000) GS:ffff8880d9c00000(0000) knlGS:0000000000000000 [ 357.866248][ T1000] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 357.867531][ T1000] CR2: 000055ce01ba8100 CR3: 00000000b7dbe005 CR4: 00000000000606f0 [ 357.868972][ T1000] Call Trace: [ 357.869423][ T1000] ? lock_contended+0xcd0/0xcd0 [ 357.870001][ T1000] ? __alloc_pages_slowpath+0x21d0/0x21d0 [ 357.870673][ T1000] ? _kstrtoull+0x76/0x160 [ 357.871148][ T1000] ? alloc_pages_current+0xc1/0x1a0 [ 357.871704][ T1000] kmalloc_order+0x22/0x80 [ 357.872184][ T1000] kmalloc_order_trace+0x1d/0x140 [ 357.872733][ T1000] __kmalloc+0x302/0x3a0 [ 357.873204][ T1000] nsim_bus_dev_numvfs_store+0x1ab/0x260 [netdevsim] [ 357.873919][ T1000] ? kernfs_get_active+0x12c/0x180 [ 357.874459][ T1000] ? new_device_store+0x450/0x450 [netdevsim] [ 357.875111][ T1000] ? kernfs_get_parent+0x70/0x70 [ 357.875632][ T1000] ? sysfs_file_ops+0x160/0x160 [ 357.876152][ T1000] kernfs_fop_write+0x276/0x410 [ 357.876680][ T1000] ? __sb_start_write+0x1ba/0x2e0 [ 357.877225][ T1000] vfs_write+0x197/0x4a0 [ 357.877671][ T1000] ksys_write+0x141/0x1d0 [ ... ] Reviewed-by: Jakub Kicinski Fixes: 79579220566c ("netdevsim: add SR-IOV functionality") Fixes: 82c93a87bf8b ("netdevsim: implement couple of testing devlink health reporters") Signed-off-by: Taehee Yoo Signed-off-by: Jakub Kicinski --- drivers/net/netdevsim/bus.c | 2 +- drivers/net/netdevsim/health.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/netdevsim/bus.c b/drivers/net/netdevsim/bus.c index e455dd1cf4d0..7971dc4f54f1 100644 --- a/drivers/net/netdevsim/bus.c +++ b/drivers/net/netdevsim/bus.c @@ -29,7 +29,7 @@ static int nsim_bus_dev_vfs_enable(struct nsim_bus_dev *nsim_bus_dev, { nsim_bus_dev->vfconfigs = kcalloc(num_vfs, sizeof(struct nsim_vf_config), - GFP_KERNEL); + GFP_KERNEL | __GFP_NOWARN); if (!nsim_bus_dev->vfconfigs) return -ENOMEM; nsim_bus_dev->num_vfs = num_vfs; diff --git a/drivers/net/netdevsim/health.c b/drivers/net/netdevsim/health.c index 30595b1299bd..ba8d9ad60feb 100644 --- a/drivers/net/netdevsim/health.c +++ b/drivers/net/netdevsim/health.c @@ -82,7 +82,7 @@ static int nsim_dev_dummy_fmsg_put(struct devlink_fmsg *fmsg, u32 binary_len) if (err) return err; - binary = kmalloc(binary_len, GFP_KERNEL); + binary = kmalloc(binary_len, GFP_KERNEL | __GFP_NOWARN); if (!binary) return -ENOMEM; get_random_bytes(binary, binary_len);