Please note that diffs are not public domain; they are subject to the copyright notices on the relevant files. =================================================================== RCS file: /ftp/cvs/cvsroot/src/sys/kern/uipc_socket.c,v rcsdiff: /ftp/cvs/cvsroot/src/sys/kern/uipc_socket.c,v: warning: Unknown phrases like `commitid ...;' are present. retrieving revision 1.177.4.3 retrieving revision 1.209.2.2 diff -u -p -r1.177.4.3 -r1.209.2.2 --- src/sys/kern/uipc_socket.c 2009/05/03 13:18:55 1.177.4.3 +++ src/sys/kern/uipc_socket.c 2013/02/14 22:13:59 1.209.2.2 @@ -1,4 +1,4 @@ -/* $NetBSD: uipc_socket.c,v 1.177.4.3 2009/05/03 13:18:55 bouyer Exp $ */ +/* $NetBSD: uipc_socket.c,v 1.209.2.2 2013/02/14 22:13:59 jdc Exp $ */ /*- * Copyright (c) 2002, 2007, 2008, 2009 The NetBSD Foundation, Inc. @@ -63,8 +63,9 @@ */ #include -__KERNEL_RCSID(0, "$NetBSD: uipc_socket.c,v 1.177.4.3 2009/05/03 13:18:55 bouyer Exp $"); +__KERNEL_RCSID(0, "$NetBSD: uipc_socket.c,v 1.209.2.2 2013/02/14 22:13:59 jdc Exp $"); +#include "opt_compat_netbsd.h" #include "opt_sock_counters.h" #include "opt_sosend_loan.h" #include "opt_mbuftrace.h" @@ -91,8 +92,16 @@ __KERNEL_RCSID(0, "$NetBSD: uipc_socket. #include #include #include +#include -#include +#ifdef COMPAT_50 +#include +#include +#endif + +#include +#include +#include MALLOC_DEFINE(M_SOOPTS, "soopts", "socket options"); MALLOC_DEFINE(M_SONAME, "soname", "socket name"); @@ -127,8 +136,6 @@ EVCNT_ATTACH_STATIC(sosend_kvalimit); #endif /* SOSEND_COUNTERS */ -static struct callback_entry sokva_reclaimerentry; - #if defined(SOSEND_NO_LOAN) || defined(MULTIPROCESSOR) int sock_loan_thresh = -1; #else @@ -136,7 +143,7 @@ int sock_loan_thresh = 4096; #endif static kmutex_t so_pendfree_lock; -static struct mbuf *so_pendfree; +static struct mbuf *so_pendfree = NULL; #ifndef SOMAXKVA #define SOMAXKVA (16 * 1024 * 1024) @@ -145,10 +152,16 @@ int somaxkva = SOMAXKVA; static int socurkva; static kcondvar_t socurkva_cv; +static kauth_listener_t socket_listener; + #define SOCK_LOAN_CHUNK 65536 -static size_t sodopendfree(void); -static size_t sodopendfreel(void); +static void sopendfree_thread(void *); +static kcondvar_t pendfree_thread_cv; +static lwp_t *sopendfree_lwp; + +static void sysctl_kern_somaxkva_setup(void); +static struct sysctllog *socket_sysctllog; static vsize_t sokvareserve(struct socket *so, vsize_t len) @@ -157,21 +170,6 @@ sokvareserve(struct socket *so, vsize_t mutex_enter(&so_pendfree_lock); while (socurkva + len > somaxkva) { - size_t freed; - - /* - * try to do pendfree. - */ - - freed = sodopendfreel(); - - /* - * if some kva was freed, try again. - */ - - if (freed) - continue; - SOSEND_COUNTER_INCR(&sosend_kvalimit); error = cv_wait_sig(&socurkva_cv, &so_pendfree_lock); if (error) { @@ -199,7 +197,7 @@ sokvaunreserve(vsize_t len) */ vaddr_t -sokvaalloc(vsize_t len, struct socket *so) +sokvaalloc(vaddr_t sva, vsize_t len, struct socket *so) { vaddr_t lva; @@ -214,7 +212,8 @@ sokvaalloc(vsize_t len, struct socket *s * allocate kva. */ - lva = uvm_km_alloc(kernel_map, len, 0, UVM_KMF_VAONLY | UVM_KMF_WAITVA); + lva = uvm_km_alloc(kernel_map, len, atop(sva) & uvmexp.colormask, + UVM_KMF_COLORMATCH | UVM_KMF_VAONLY | UVM_KMF_WAITVA); if (lva == 0) { sokvaunreserve(len); return (0); @@ -264,56 +263,45 @@ sodoloanfree(struct vm_page **pgs, void sokvafree(sva, len); } -static size_t -sodopendfree(void) -{ - size_t rv; - - if (__predict_true(so_pendfree == NULL)) - return 0; - - mutex_enter(&so_pendfree_lock); - rv = sodopendfreel(); - mutex_exit(&so_pendfree_lock); - - return rv; -} - /* - * sodopendfreel: free mbufs on "pendfree" list. + * sopendfree_thread: free mbufs on "pendfree" list. * unlock and relock so_pendfree_lock when freeing mbufs. - * - * => called with so_pendfree_lock held. */ -static size_t -sodopendfreel(void) +static void +sopendfree_thread(void *v) { struct mbuf *m, *next; - size_t rv = 0; - - KASSERT(mutex_owned(&so_pendfree_lock)); + size_t rv; - while (so_pendfree != NULL) { - m = so_pendfree; - so_pendfree = NULL; - mutex_exit(&so_pendfree_lock); + mutex_enter(&so_pendfree_lock); - for (; m != NULL; m = next) { - next = m->m_next; - KASSERT((~m->m_flags & (M_EXT|M_EXT_PAGES)) == 0); - KASSERT(m->m_ext.ext_refcnt == 0); + for (;;) { + rv = 0; + while (so_pendfree != NULL) { + m = so_pendfree; + so_pendfree = NULL; + mutex_exit(&so_pendfree_lock); + + for (; m != NULL; m = next) { + next = m->m_next; + KASSERT((~m->m_flags & (M_EXT|M_EXT_PAGES)) == 0); + KASSERT(m->m_ext.ext_refcnt == 0); + + rv += m->m_ext.ext_size; + sodoloanfree(m->m_ext.ext_pgs, m->m_ext.ext_buf, + m->m_ext.ext_size); + pool_cache_put(mb_cache, m); + } - rv += m->m_ext.ext_size; - sodoloanfree(m->m_ext.ext_pgs, m->m_ext.ext_buf, - m->m_ext.ext_size); - pool_cache_put(mb_cache, m); + mutex_enter(&so_pendfree_lock); } - - mutex_enter(&so_pendfree_lock); + if (rv) + cv_broadcast(&socurkva_cv); + cv_wait(&pendfree_thread_cv, &so_pendfree_lock); } - - return (rv); + panic("sopendfree_thread"); + /* NOTREACHED */ } void @@ -332,7 +320,7 @@ soloanfree(struct mbuf *m, void *buf, si mutex_enter(&so_pendfree_lock); m->m_next = so_pendfree; so_pendfree = m; - cv_broadcast(&socurkva_cv); + cv_signal(&pendfree_thread_cv); mutex_exit(&so_pendfree_lock); } @@ -362,7 +350,7 @@ sosend_loan(struct socket *so, struct ui KASSERT(npgs <= M_EXT_MAXPAGES); - lva = sokvaalloc(len, so); + lva = sokvaalloc(sva, len, so); if (lva == 0) return 0; @@ -375,7 +363,7 @@ sosend_loan(struct socket *so, struct ui for (i = 0, va = lva; i < npgs; i++, va += PAGE_SIZE) pmap_kenter_pa(va, VM_PAGE_TO_PHYS(m->m_ext.ext_pgs[i]), - VM_PROT_READ); + VM_PROT_READ, 0); pmap_update(pmap_kernel()); lva += (vaddr_t) iov->iov_base & PAGE_MASK; @@ -395,20 +383,6 @@ sosend_loan(struct socket *so, struct ui return (space); } -static int -sokva_reclaim_callback(struct callback_entry *ce, void *obj, void *arg) -{ - - KASSERT(ce == &sokva_reclaimerentry); - KASSERT(obj == NULL); - - sodopendfree(); - if (!vm_map_starved_p(kernel_map)) { - return CALLBACK_CHAIN_ABORT; - } - return CALLBACK_CHAIN_CONTINUE; -} - struct mbuf * getsombuf(struct socket *so, int type) { @@ -419,21 +393,89 @@ getsombuf(struct socket *so, int type) return m; } +static int +socket_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, + void *arg0, void *arg1, void *arg2, void *arg3) +{ + int result; + enum kauth_network_req req; + + result = KAUTH_RESULT_DEFER; + req = (enum kauth_network_req)arg0; + + if ((action != KAUTH_NETWORK_SOCKET) && + (action != KAUTH_NETWORK_BIND)) + return result; + + switch (req) { + case KAUTH_REQ_NETWORK_BIND_PORT: + result = KAUTH_RESULT_ALLOW; + break; + + case KAUTH_REQ_NETWORK_SOCKET_DROP: { + /* Normal users can only drop their own connections. */ + struct socket *so = (struct socket *)arg1; + + if (proc_uidmatch(cred, so->so_cred)) + result = KAUTH_RESULT_ALLOW; + + break; + } + + case KAUTH_REQ_NETWORK_SOCKET_OPEN: + /* We allow "raw" routing/bluetooth sockets to anyone. */ + if ((u_long)arg1 == PF_ROUTE || (u_long)arg1 == PF_OROUTE + || (u_long)arg1 == PF_BLUETOOTH) { + result = KAUTH_RESULT_ALLOW; + } else { + /* Privileged, let secmodel handle this. */ + if ((u_long)arg2 == SOCK_RAW) + break; + } + + result = KAUTH_RESULT_ALLOW; + + break; + + case KAUTH_REQ_NETWORK_SOCKET_CANSEE: + result = KAUTH_RESULT_ALLOW; + + break; + + default: + break; + } + + return result; +} + void soinit(void) { + sysctl_kern_somaxkva_setup(); + mutex_init(&so_pendfree_lock, MUTEX_DEFAULT, IPL_VM); softnet_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE); cv_init(&socurkva_cv, "sokva"); + cv_init(&pendfree_thread_cv, "sopendfr"); soinit2(); /* Set the initial adjusted socket buffer size. */ if (sb_max_set(sb_max)) panic("bad initial sb_max value: %lu", sb_max); - callback_register(&vm_map_to_kernel(kernel_map)->vmk_reclaim_callback, - &sokva_reclaimerentry, NULL, sokva_reclaim_callback); + socket_listener = kauth_listen_scope(KAUTH_SCOPE_NETWORK, + socket_listener_cb, NULL); +} + +void +soinit1(void) +{ + int error = kthread_create(PRI_NONE, KTHREAD_MPSAFE, NULL, + sopendfree_thread, NULL, &sopendfree_lwp, "sopendfree"); + if (error) + panic("soinit1 %d", error); } /* @@ -490,7 +532,6 @@ socreate(int dom, struct socket **aso, i #endif uid = kauth_cred_geteuid(l->l_cred); so->so_uidinfo = uid_find(uid); - so->so_egid = kauth_cred_getegid(l->l_cred); so->so_cpid = l->l_proc->p_pid; if (lockso != NULL) { /* Caller wants us to share a lock. */ @@ -509,6 +550,7 @@ socreate(int dom, struct socket **aso, i sofree(so); return error; } + so->so_cred = kauth_cred_dup(l->l_cred); sounlock(so); *aso = so; return 0; @@ -524,10 +566,14 @@ fsocreate(int domain, struct socket **so struct socket *so; struct file *fp; int fd, error; + int flags = type & SOCK_FLAGS_MASK; + type &= ~SOCK_FLAGS_MASK; if ((error = fd_allocfile(&fp, &fd)) != 0) - return (error); - fp->f_flag = FREAD|FWRITE; + return error; + fd_set_exclose(l, fd, (flags & SOCK_CLOEXEC) != 0); + fp->f_flag = FREAD|FWRITE|((flags & SOCK_NONBLOCK) ? FNONBLOCK : 0)| + ((flags & SOCK_NOSIGPIPE) ? FNOSIGPIPE : 0); fp->f_type = DTYPE_SOCKET; fp->f_ops = &socketops; error = socreate(domain, &so, type, protocol, l, NULL); @@ -539,11 +585,26 @@ fsocreate(int domain, struct socket **so fp->f_data = so; fd_affix(curproc, fp, fd); *fdout = fd; + if (flags & SOCK_NONBLOCK) + so->so_state |= SS_NBIO; } return error; } int +sofamily(const struct socket *so) +{ + const struct protosw *pr; + const struct domain *dom; + + if ((pr = so->so_proto) == NULL) + return AF_UNSPEC; + if ((dom = pr->pr_domain) == NULL) + return AF_UNSPEC; + return dom->dom_family; +} + +int sobind(struct socket *so, struct mbuf *nam, struct lwp *l) { int error; @@ -666,7 +727,8 @@ soclose(struct socket *so) goto drop; } if (so->so_options & SO_LINGER) { - if ((so->so_state & SS_ISDISCONNECTING) && so->so_nbio) + if ((so->so_state & (SS_ISDISCONNECTING|SS_NBIO)) == + (SS_ISDISCONNECTING|SS_NBIO)) goto drop; while (so->so_state & SS_ISCONNECTED) { error = sowait(so, true, so->so_linger * hz); @@ -685,6 +747,7 @@ soclose(struct socket *so) discard: if (so->so_state & SS_NOFDREF) panic("soclose: NOFDREF"); + kauth_cred_free(so->so_cred); so->so_state |= SS_NOFDREF; sofree(so); return (error); @@ -787,7 +850,6 @@ sodisconnect(struct socket *so) error = (*so->so_proto->pr_usrreq)(so, PRU_DISCONNECT, NULL, NULL, NULL, NULL); } - sodopendfree(); return (error); } @@ -817,9 +879,9 @@ sosend(struct socket *so, struct mbuf *a struct proc *p; long space, len, resid, clen, mlen; int error, s, dontroute, atomic; + short wakeup_state = 0; p = l->l_proc; - sodopendfree(); clen = 0; /* @@ -886,16 +948,22 @@ sosend(struct socket *so, struct mbuf *a } if (space < resid + clen && (atomic || space < so->so_snd.sb_lowat || space < clen)) { - if (so->so_nbio) { + if ((so->so_state & SS_NBIO) || (flags & MSG_NBIO)) { error = EWOULDBLOCK; goto release; } sbunlock(&so->so_snd); + if (wakeup_state & SS_RESTARTSYS) { + error = ERESTART; + goto out; + } error = sbwait(&so->so_snd); if (error) goto out; + wakeup_state = so->so_state; goto restart; } + wakeup_state = 0; mp = ⊤ space -= clen; do { @@ -930,7 +998,7 @@ sosend(struct socket *so, struct mbuf *a } if (resid >= MINCLSIZE && space >= MCLBYTES) { SOSEND_COUNTER_INCR(&sosend_copy_big); - m_clget(m, M_WAIT); + m_clget(m, M_DONTWAIT); if ((m->m_flags & M_EXT) == 0) goto nopages; mlen = MCLBYTES; @@ -1066,11 +1134,13 @@ soreceive(struct socket *so, struct mbuf { struct lwp *l = curlwp; struct mbuf *m, **mp, *mt; - int atomic, flags, len, error, s, offset, moff, type, orig_resid; + size_t len, offset, moff, orig_resid; + int atomic, flags, error, s, type; const struct protosw *pr; struct mbuf *nextrecord; int mbuf_removed = 0; const struct domain *dom; + short wakeup_state = 0; pr = so->so_proto; atomic = pr->pr_flags & PR_ATOMIC; @@ -1088,9 +1158,6 @@ soreceive(struct socket *so, struct mbuf else flags = 0; - if ((flags & MSG_DONTWAIT) == 0) - sodopendfree(); - if (flags & MSG_OOB) { m = m_get(M_WAIT, MT_DATA); solock(so); @@ -1101,7 +1168,7 @@ soreceive(struct socket *so, struct mbuf goto bad; do { error = uiomove(mtod(m, void *), - (int) min(uio->uio_resid, m->m_len), uio); + MIN(uio->uio_resid, m->m_len), uio); m = m_free(m); } while (uio->uio_resid > 0 && error == 0 && m); bad: @@ -1178,19 +1245,24 @@ soreceive(struct socket *so, struct mbuf } if (uio->uio_resid == 0) goto release; - if (so->so_nbio || (flags & MSG_DONTWAIT)) { + if ((so->so_state & SS_NBIO) || + (flags & (MSG_DONTWAIT|MSG_NBIO))) { error = EWOULDBLOCK; goto release; } SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 1"); SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 1"); sbunlock(&so->so_rcv); - error = sbwait(&so->so_rcv); + if (wakeup_state & SS_RESTARTSYS) + error = ERESTART; + else + error = sbwait(&so->so_rcv); if (error != 0) { sounlock(so); splx(s); return error; } + wakeup_state = so->so_state; goto restart; } dontblock: @@ -1279,7 +1351,9 @@ soreceive(struct socket *so, struct mbuf type == SCM_RIGHTS) { sounlock(so); splx(s); - error = (*dom->dom_externalize)(cm, l); + error = (*dom->dom_externalize)(cm, l, + (flags & MSG_CMSG_CLOEXEC) ? + O_CLOEXEC : 0); s = splsoftnet(); solock(so); } @@ -1329,6 +1403,7 @@ soreceive(struct socket *so, struct mbuf panic("receive 3"); #endif so->so_state &= ~SS_RCVATMARK; + wakeup_state = 0; len = uio->uio_resid; if (so->so_oobmark && len > so->so_oobmark - offset) len = so->so_oobmark - offset; @@ -1347,7 +1422,7 @@ soreceive(struct socket *so, struct mbuf SBLASTMBUFCHK(&so->so_rcv, "soreceive uiomove"); sounlock(so); splx(s); - error = uiomove(mtod(m, char *) + moff, (int)len, uio); + error = uiomove(mtod(m, char *) + moff, len, uio); s = splsoftnet(); solock(so); if (error != 0) { @@ -1461,7 +1536,10 @@ soreceive(struct socket *so, struct mbuf NULL, (struct mbuf *)(long)flags, NULL, l); SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 2"); SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 2"); - error = sbwait(&so->so_rcv); + if (wakeup_state & SS_RESTARTSYS) + error = ERESTART; + else + error = sbwait(&so->so_rcv); if (error != 0) { sbunlock(&so->so_rcv); sounlock(so); @@ -1470,6 +1548,7 @@ soreceive(struct socket *so, struct mbuf } if ((m = so->so_rcv.sb_mb) != NULL) nextrecord = m->m_nextpkt; + wakeup_state = so->so_state; } } @@ -1536,18 +1615,23 @@ soshutdown(struct socket *so, int how) return error; } -int -sodrain(struct socket *so) +void +sorestart(struct socket *so) { - int error; - + /* + * An application has called close() on an fd on which another + * of its threads has called a socket system call. + * Mark this and wake everyone up, and code that would block again + * instead returns ERESTART. + * On system call re-entry the fd is validated and EBADF returned. + * Any other fd will block again on the 2nd syscall. + */ solock(so); - so->so_state |= SS_ISDRAINING; + so->so_state |= SS_RESTARTSYS; cv_broadcast(&so->so_cv); - error = soshutdown(so, SHUT_RDWR); + cv_broadcast(&so->so_snd.sb_cv); + cv_broadcast(&so->so_rcv.sb_cv); sounlock(so); - - return error; } void @@ -1585,11 +1669,11 @@ sorflush(struct socket *so) static int sosetopt1(struct socket *so, const struct sockopt *sopt) { - int error, optval; + int error = EINVAL, optval, opt; struct linger l; struct timeval tv; - switch (sopt->sopt_name) { + switch ((opt = sopt->sopt_name)) { case SO_ACCEPTFILTER: error = accept_filt_setopt(so, sopt); @@ -1622,14 +1706,18 @@ sosetopt1(struct socket *so, const struc case SO_REUSEPORT: case SO_OOBINLINE: case SO_TIMESTAMP: + case SO_NOSIGPIPE: +#ifdef SO_OTIMESTAMP + case SO_OTIMESTAMP: +#endif error = sockopt_getint(sopt, &optval); solock(so); if (error) break; if (optval) - so->so_options |= sopt->sopt_name; + so->so_options |= opt; else - so->so_options &= ~sopt->sopt_name; + so->so_options &= ~opt; break; case SO_SNDBUF: @@ -1650,7 +1738,7 @@ sosetopt1(struct socket *so, const struc break; } - switch (sopt->sopt_name) { + switch (opt) { case SO_SNDBUF: if (sbreserve(&so->so_snd, (u_long)optval, so) == 0) { error = ENOBUFS; @@ -1687,9 +1775,26 @@ sosetopt1(struct socket *so, const struc } break; +#ifdef COMPAT_50 + case SO_OSNDTIMEO: + case SO_ORCVTIMEO: { + struct timeval50 otv; + error = sockopt_get(sopt, &otv, sizeof(otv)); + if (error) { + solock(so); + break; + } + timeval50_to_timeval(&otv, &tv); + opt = opt == SO_OSNDTIMEO ? SO_SNDTIMEO : SO_RCVTIMEO; + error = 0; + /*FALLTHROUGH*/ + } +#endif /* COMPAT_50 */ + case SO_SNDTIMEO: case SO_RCVTIMEO: - error = sockopt_get(sopt, &tv, sizeof(tv)); + if (error) + error = sockopt_get(sopt, &tv, sizeof(tv)); solock(so); if (error) break; @@ -1703,7 +1808,7 @@ sosetopt1(struct socket *so, const struc if (optval == 0 && tv.tv_usec != 0) optval = 1; - switch (sopt->sopt_name) { + switch (opt) { case SO_SNDTIMEO: so->so_snd.sb_timeo = optval; break; @@ -1776,11 +1881,11 @@ so_setsockopt(struct lwp *l, struct sock static int sogetopt1(struct socket *so, struct sockopt *sopt) { - int error, optval; + int error, optval, opt; struct linger l; struct timeval tv; - switch (sopt->sopt_name) { + switch ((opt = sopt->sopt_name)) { case SO_ACCEPTFILTER: error = accept_filt_getopt(so, sopt); @@ -1802,8 +1907,11 @@ sogetopt1(struct socket *so, struct sock case SO_BROADCAST: case SO_OOBINLINE: case SO_TIMESTAMP: - error = sockopt_setint(sopt, - (so->so_options & sopt->sopt_name) ? 1 : 0); + case SO_NOSIGPIPE: +#ifdef SO_OTIMESTAMP + case SO_OTIMESTAMP: +#endif + error = sockopt_setint(sopt, (so->so_options & opt) ? 1 : 0); break; case SO_TYPE: @@ -1831,9 +1939,25 @@ sogetopt1(struct socket *so, struct sock error = sockopt_setint(sopt, so->so_rcv.sb_lowat); break; +#ifdef COMPAT_50 + case SO_OSNDTIMEO: + case SO_ORCVTIMEO: { + struct timeval50 otv; + + optval = (opt == SO_OSNDTIMEO ? + so->so_snd.sb_timeo : so->so_rcv.sb_timeo); + + otv.tv_sec = optval / hz; + otv.tv_usec = (optval % hz) * tick; + + error = sockopt_set(sopt, &otv, sizeof(otv)); + break; + } +#endif /* COMPAT_50 */ + case SO_SNDTIMEO: case SO_RCVTIMEO: - optval = (sopt->sopt_name == SO_SNDTIMEO ? + optval = (opt == SO_SNDTIMEO ? so->so_snd.sb_timeo : so->so_rcv.sb_timeo); tv.tv_sec = optval / hz; @@ -2274,16 +2398,18 @@ sysctl_kern_somaxkva(SYSCTLFN_ARGS) return (error); } -SYSCTL_SETUP(sysctl_kern_somaxkva_setup, "sysctl kern.somaxkva setup") +static void +sysctl_kern_somaxkva_setup(void) { - sysctl_createv(clog, 0, NULL, NULL, + KASSERT(socket_sysctllog == NULL); + sysctl_createv(&socket_sysctllog, 0, NULL, NULL, CTLFLAG_PERMANENT, CTLTYPE_NODE, "kern", NULL, NULL, 0, NULL, 0, CTL_KERN, CTL_EOL); - sysctl_createv(clog, 0, NULL, NULL, + sysctl_createv(&socket_sysctllog, 0, NULL, NULL, CTLFLAG_PERMANENT|CTLFLAG_READWRITE, CTLTYPE_INT, "somaxkva", SYSCTL_DESCR("Maximum amount of kernel memory to be "