From: Chuck Lever chuck.lever@oracle.com
commit 7827c81f0248e3c2f40d438b020f3d222f002171 upstream.
The premise that "Once an svc thread is scheduled and executing an RPC, no other processes will touch svc_rqst::rq_flags" is false. svc_xprt_enqueue() examines the RQ_BUSY flag in scheduled nfsd threads when determining which thread to wake up next.
Found via KCSAN.
Fixes: 28df0988815f ("SUNRPC: Use RMW bitops in single-threaded hot paths") Reviewed-by: Jeff Layton jlayton@kernel.org Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/nfsd/nfs4proc.c | 7 +++---- fs/nfsd/nfs4xdr.c | 2 +- net/sunrpc/auth_gss/svcauth_gss.c | 4 ++-- net/sunrpc/svc.c | 6 +++--- net/sunrpc/svc_xprt.c | 2 +- net/sunrpc/svcsock.c | 8 ++++---- net/sunrpc/xprtrdma/svc_rdma_transport.c | 2 +- 7 files changed, 15 insertions(+), 16 deletions(-)
--- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -928,7 +928,7 @@ nfsd4_read(struct svc_rqst *rqstp, struc * the client wants us to do more in this compound: */ if (!nfsd4_last_compound_op(rqstp)) - __clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags); + clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
/* check stateid */ status = nfs4_preprocess_stateid_op(rqstp, cstate, &cstate->current_fh, @@ -2615,12 +2615,11 @@ nfsd4_proc_compound(struct svc_rqst *rqs cstate->minorversion = args->minorversion; fh_init(current_fh, NFS4_FHSIZE); fh_init(save_fh, NFS4_FHSIZE); - /* * Don't use the deferral mechanism for NFSv4; compounds make it * too hard to avoid non-idempotency problems. */ - __clear_bit(RQ_USEDEFERRAL, &rqstp->rq_flags); + clear_bit(RQ_USEDEFERRAL, &rqstp->rq_flags);
/* * According to RFC3010, this takes precedence over all other errors. @@ -2742,7 +2741,7 @@ encode_op: out: cstate->status = status; /* Reset deferral mechanism for RPC deferrals */ - __set_bit(RQ_USEDEFERRAL, &rqstp->rq_flags); + set_bit(RQ_USEDEFERRAL, &rqstp->rq_flags); return rpc_success; }
--- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -2464,7 +2464,7 @@ nfsd4_decode_compound(struct nfsd4_compo argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
if (readcount > 1 || max_reply > PAGE_SIZE - auth_slack) - __clear_bit(RQ_SPLICE_OK, &argp->rqstp->rq_flags); + clear_bit(RQ_SPLICE_OK, &argp->rqstp->rq_flags);
return true; } --- a/net/sunrpc/auth_gss/svcauth_gss.c +++ b/net/sunrpc/auth_gss/svcauth_gss.c @@ -900,7 +900,7 @@ unwrap_integ_data(struct svc_rqst *rqstp * rejecting the server-computed MIC in this somewhat rare case, * do not use splice with the GSS integrity service. */ - __clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags); + clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
/* Did we already verify the signature on the original pass through? */ if (rqstp->rq_deferred) @@ -972,7 +972,7 @@ unwrap_priv_data(struct svc_rqst *rqstp, int pad, remaining_len, offset; u32 rseqno;
- __clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags); + clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
priv_len = svc_getnl(&buf->head[0]); if (rqstp->rq_deferred) { --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -1244,10 +1244,10 @@ svc_process_common(struct svc_rqst *rqst goto err_short_len;
/* Will be turned off by GSS integrity and privacy services */ - __set_bit(RQ_SPLICE_OK, &rqstp->rq_flags); + set_bit(RQ_SPLICE_OK, &rqstp->rq_flags); /* Will be turned off only when NFSv4 Sessions are used */ - __set_bit(RQ_USEDEFERRAL, &rqstp->rq_flags); - __clear_bit(RQ_DROPME, &rqstp->rq_flags); + set_bit(RQ_USEDEFERRAL, &rqstp->rq_flags); + clear_bit(RQ_DROPME, &rqstp->rq_flags);
svc_putu32(resv, rqstp->rq_xid);
--- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -1238,7 +1238,7 @@ static struct cache_deferred_req *svc_de trace_svc_defer(rqstp); svc_xprt_get(rqstp->rq_xprt); dr->xprt = rqstp->rq_xprt; - __set_bit(RQ_DROPME, &rqstp->rq_flags); + set_bit(RQ_DROPME, &rqstp->rq_flags);
dr->handle.revisit = svc_revisit; return &dr->handle; --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -298,9 +298,9 @@ static void svc_sock_setbufsize(struct s static void svc_sock_secure_port(struct svc_rqst *rqstp) { if (svc_port_is_privileged(svc_addr(rqstp))) - __set_bit(RQ_SECURE, &rqstp->rq_flags); + set_bit(RQ_SECURE, &rqstp->rq_flags); else - __clear_bit(RQ_SECURE, &rqstp->rq_flags); + clear_bit(RQ_SECURE, &rqstp->rq_flags); }
/* @@ -1008,9 +1008,9 @@ static int svc_tcp_recvfrom(struct svc_r rqstp->rq_xprt_ctxt = NULL; rqstp->rq_prot = IPPROTO_TCP; if (test_bit(XPT_LOCAL, &svsk->sk_xprt.xpt_flags)) - __set_bit(RQ_LOCAL, &rqstp->rq_flags); + set_bit(RQ_LOCAL, &rqstp->rq_flags); else - __clear_bit(RQ_LOCAL, &rqstp->rq_flags); + clear_bit(RQ_LOCAL, &rqstp->rq_flags);
p = (__be32 *)rqstp->rq_arg.head[0].iov_base; calldir = p[1]; --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c @@ -602,7 +602,7 @@ static int svc_rdma_has_wspace(struct sv
static void svc_rdma_secure_port(struct svc_rqst *rqstp) { - __set_bit(RQ_SECURE, &rqstp->rq_flags); + set_bit(RQ_SECURE, &rqstp->rq_flags); }
static void svc_rdma_kill_temp_xprt(struct svc_xprt *xprt)