From: Chuck Lever <chuck.lever@xxxxxxxxxx>
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")
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
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(-)
diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index bd880d55f565..9b81d012666e 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -937,7 +937,7 @@ nfsd4_read(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
* 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,
@@ -2607,12 +2607,11 @@ nfsd4_proc_compound(struct svc_rqst *rqstp)
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.
@@ -2734,7 +2733,7 @@ nfsd4_proc_compound(struct svc_rqst *rqstp)
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;
}
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index ebb4d02a42ce..97edb32be77f 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -2523,7 +2523,7 @@ nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
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;
}
diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index 148bb0a7fa5b..acb822b23af1 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -923,7 +923,7 @@ unwrap_integ_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct g
* 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)
@@ -990,7 +990,7 @@ unwrap_priv_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gs
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) {
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 8f1b596db33f..b1da586c4476 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -1243,10 +1243,10 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv)
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);
diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index 2106003645a7..c2ce12538008 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -1238,7 +1238,7 @@ static struct cache_deferred_req *svc_defer(struct cache_req *req)
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;
diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index 2fc98fea59b4..e833103f4629 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -298,9 +298,9 @@ static void svc_sock_setbufsize(struct svc_sock *svsk, unsigned int nreqs)
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_rqst *rqstp)
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];
diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c
index 199fa012f18a..94b20fb47135 100644
--- 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 svc_xprt *xprt)
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)
