diff options
| author | riastradh <riastradh@NetBSD.org> | 2021-06-16 00:21:17 +0000 |
|---|---|---|
| committer | riastradh <riastradh@NetBSD.org> | 2021-06-16 00:21:17 +0000 |
| commit | bbdda93be2f0bfefe91466b398fe42700a6ea284 (patch) | |
| tree | e75e77046575209dbb21f73d0bc44c61ec0ec6c0 /sys/net/if_vlan.c | |
| parent | 5a96957fa793651c8e7093a5a4c2fcae87232af2 (diff) | |
if_attach and if_initialize cannot fail, don't test return value
These were originally made failable back in 2017 when if_initialize
allocated a softint in every interface for link state changes, so
that it could fail gracefully instead of panicking:
https://mail-index.NetBSD.org/source-changes/2017/10/23/msg089053.html
However, this spawned many seldom- or never-tested error branches,
which are risky to have around. And that softint in every interface
has since been replaced by a single global workqueue, because link
state changes require thread context but not low latency or high
throughput:
https://mail-index.NetBSD.org/source-changes/2020/02/06/msg113759.html
So there is no longer any reason for if_initialize to fail. (The
subroutine if_stats_init can't fail because percpu_alloc can't fail
either.)
There is a snag: the softint_establish in if_percpuq_create could
fail, potentially leading to bad consequences later on trying to use
the softint. This change doesn't introduce any new bugs because of
the snag -- if_percpuq_attach was already broken. However, the snag
can be better addressed without spawning error branches, either by
using a single softint or making softints less scarce.
(Separate commit will change the signatures of if_attach and
if_initialize to return void, scheduled to ride whatever is the next
convenient kernel bump.)
Patch and testing on amd64 and evbmips64-eb by maya@; commit message
soliloquy, and compile-testing on evbppc/i386/earmv7hf, by me.
Diffstat (limited to 'sys/net/if_vlan.c')
| -rw-r--r-- | sys/net/if_vlan.c | 26 |
1 files changed, 3 insertions, 23 deletions
diff --git a/sys/net/if_vlan.c b/sys/net/if_vlan.c index 7901267f805..33eabe4a6f4 100644 --- a/sys/net/if_vlan.c +++ b/sys/net/if_vlan.c @@ -1,4 +1,4 @@ -/* $NetBSD: if_vlan.c,v 1.153 2020/09/26 18:38:09 roy Exp $ */ +/* $NetBSD: if_vlan.c,v 1.154 2021/06/16 00:21:19 riastradh Exp $ */ /* * Copyright (c) 2000, 2001 The NetBSD Foundation, Inc. @@ -78,7 +78,7 @@ */ #include <sys/cdefs.h> -__KERNEL_RCSID(0, "$NetBSD: if_vlan.c,v 1.153 2020/09/26 18:38:09 roy Exp $"); +__KERNEL_RCSID(0, "$NetBSD: if_vlan.c,v 1.154 2021/06/16 00:21:19 riastradh Exp $"); #ifdef _KERNEL_OPT #include "opt_inet.h" @@ -333,7 +333,6 @@ vlan_clone_create(struct if_clone *ifc, int unit) struct ifvlan *ifv; struct ifnet *ifp; struct ifvlan_linkmib *mib; - int rv; ifv = malloc(sizeof(struct ifvlan), M_DEVBUF, M_WAITOK | M_ZERO); mib = kmem_zalloc(sizeof(struct ifvlan_linkmib), KM_SLEEP); @@ -362,14 +361,7 @@ vlan_clone_create(struct if_clone *ifc, int unit) ifp->if_transmit = vlan_transmit; ifp->if_ioctl = vlan_ioctl; IFQ_SET_READY(&ifp->if_snd); - - rv = if_initialize(ifp); - if (rv != 0) { - aprint_error("%s: if_initialize failed(%d)\n", ifp->if_xname, - rv); - goto fail; - } - + if_initialize(ifp); /* * Set the link state to down. * When the parent interface attaches we will use that link state. @@ -380,18 +372,6 @@ vlan_clone_create(struct if_clone *ifc, int unit) vlan_reset_linkname(ifp); if_register(ifp); return 0; - -fail: - mutex_enter(&ifv_list.lock); - LIST_REMOVE(ifv, ifv_list); - mutex_exit(&ifv_list.lock); - - mutex_destroy(&ifv->ifv_lock); - psref_target_destroy(&ifv->ifv_mib->ifvm_psref, ifvm_psref_class); - kmem_free(ifv->ifv_mib, sizeof(struct ifvlan_linkmib)); - free(ifv, M_DEVBUF); - - return rv; } static int |
