From: "Michael J. Ruhl" <michael.j.ruhl@intel.com>
Date: Fri, 9 Jun 2017 16:00:19 -0700
Subject: IB/hfi1: Resolve kernel panics by reference counting receive contexts
Patch-mainline: v4.14-rc1
Git-commit: f683c80ca68e087b55c6f9ab6ca6beb88ebc6d69
References: bsc#1060463 FATE#323043
Base receive contexts can be used by sub contexts. Because of this,
resources for the context cannot be completely freed until all sub
contexts are done using the base context.
Introduce a reference count so that the base receive context can be
freed only when all sub contexts are done with it.
Use the provided function call for setting default send context
integrity rather than the manual method.
The cleanup path does not set all variables back to NULL after freeing
resources. Since the clean up code can get called more than once,
(e.g. during context close and on the error path), it is necessary to
make sure that all the variables are NULLed.
Possible crash are:
BUG: unable to handle kernel paging request at 0000000001908900
IP: read_csr+0x24/0x30 [hfi1]
RIP: 0010:read_csr+0x24/0x30 [hfi1]
Call Trace:
sc_disable+0x40/0x110 [hfi1]
hfi1_file_close+0x16f/0x360 [hfi1]
__fput+0xe7/0x210
____fput+0xe/0x10
or
kernel BUG at mm/slub.c:3877!
RIP: 0010:kfree+0x14f/0x170
Call Trace:
hfi1_free_ctxtdata+0x19a/0x2b0 [hfi1]
? hfi1_user_exp_rcv_grp_free+0x73/0x80 [hfi1]
hfi1_file_close+0x20f/0x360 [hfi1]
__fput+0xe7/0x210
____fput+0xe/0x10
Fixes: Commit 62239fc6e554 ("IB/hfi1: Clean up on context initialization failure")
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Sebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/infiniband/hw/hfi1/file_ops.c | 39 ++++++++++++++--------
drivers/infiniband/hw/hfi1/hfi.h | 11 ++----
drivers/infiniband/hw/hfi1/init.c | 58 +++++++++++++++++++++++++++------
drivers/infiniband/hw/hfi1/vnic_main.c | 11 +++---
4 files changed, 85 insertions(+), 34 deletions(-)
--- a/drivers/infiniband/hw/hfi1/file_ops.c
+++ b/drivers/infiniband/hw/hfi1/file_ops.c
@@ -774,6 +774,8 @@ static int hfi1_file_close(struct inode
*ev = 0;
__clear_bit(fdata->subctxt, uctxt->in_use_ctxts);
+ fdata->uctxt = NULL;
+ hfi1_rcd_put(uctxt); /* fdata reference */
if (!bitmap_empty(uctxt->in_use_ctxts, HFI1_MAX_SHARED_CTXTS)) {
mutex_unlock(&hfi1_mutex);
goto done;
@@ -794,16 +796,15 @@ static int hfi1_file_close(struct inode
/* Clear the context's J_KEY */
hfi1_clear_ctxt_jkey(dd, uctxt->ctxt);
/*
- * Reset context integrity checks to default.
- * (writes to CSRs probably belong in chip.c)
+ * If a send context is allocated, reset context integrity
+ * checks to default and disable the send context.
*/
- write_kctxt_csr(dd, uctxt->sc->hw_context, SEND_CTXT_CHECK_ENABLE,
- hfi1_pkt_default_send_ctxt_mask(dd, uctxt->sc->type));
- sc_disable(uctxt->sc);
+ if (uctxt->sc) {
+ set_pio_integrity(uctxt->sc);
+ sc_disable(uctxt->sc);
+ }
spin_unlock_irqrestore(&dd->uctxt_lock, flags);
- dd->rcd[uctxt->ctxt] = NULL;
-
hfi1_free_ctxt_rcv_groups(uctxt);
hfi1_clear_ctxt_pkey(dd, uctxt);
@@ -816,8 +817,11 @@ static int hfi1_file_close(struct inode
hfi1_stats.sps_ctxts--;
if (++dd->freectxts == dd->num_user_contexts)
aspm_enable_all(dd);
+
+ /* _rcd_put() should be done after releasing mutex */
+ dd->rcd[uctxt->ctxt] = NULL;
mutex_unlock(&hfi1_mutex);
- hfi1_free_ctxtdata(dd, uctxt);
+ hfi1_rcd_put(uctxt); /* dd reference */
done:
mmdrop(fdata->mm);
kobject_put(&dd->kobj);
@@ -887,16 +891,17 @@ static int assign_ctxt(struct hfi1_filed
ret = wait_event_interruptible(fd->uctxt->wait, !test_bit(
HFI1_CTXT_BASE_UNINIT,
&fd->uctxt->event_flags));
- if (test_bit(HFI1_CTXT_BASE_FAILED, &fd->uctxt->event_flags)) {
- clear_bit(fd->subctxt, fd->uctxt->in_use_ctxts);
- return -ENOMEM;
- }
+ if (test_bit(HFI1_CTXT_BASE_FAILED, &fd->uctxt->event_flags))
+ ret = -ENOMEM;
+
/* The only thing a sub context needs is the user_xxx stuff */
if (!ret)
ret = init_user_ctxt(fd);
- if (ret)
+ if (ret) {
clear_bit(fd->subctxt, fd->uctxt->in_use_ctxts);
+ hfi1_rcd_put(fd->uctxt);
+ }
} else if (!ret) {
ret = setup_base_ctxt(fd);
if (fd->uctxt->subctxt_cnt) {
@@ -961,6 +966,8 @@ static int find_sub_ctxt(struct hfi1_fil
fd->uctxt = uctxt;
fd->subctxt = subctxt;
+
+ hfi1_rcd_get(uctxt);
__set_bit(fd->subctxt, uctxt->in_use_ctxts);
return 1;
@@ -1069,11 +1076,14 @@ static int allocate_ctxt(struct hfi1_fil
aspm_disable_all(dd);
fd->uctxt = uctxt;
+ /* Count the reference for the fd */
+ hfi1_rcd_get(uctxt);
+
return 0;
ctxdata_free:
dd->rcd[ctxt] = NULL;
- hfi1_free_ctxtdata(dd, uctxt);
+ hfi1_rcd_put(uctxt);
return ret;
}
@@ -1273,6 +1283,7 @@ static int setup_base_ctxt(struct hfi1_f
return 0;
setup_failed:
+ /* Call _free_ctxtdata, not _rcd_put(). We still need the context. */
hfi1_free_ctxtdata(dd, uctxt);
return ret;
}
--- a/drivers/infiniband/hw/hfi1/hfi.h
+++ b/drivers/infiniband/hw/hfi1/hfi.h
@@ -213,11 +213,9 @@ struct hfi1_ctxtdata {
/* dynamic receive available interrupt timeout */
u32 rcvavail_timeout;
- /*
- * number of opens (including slave sub-contexts) on this instance
- * (ignoring forks, dup, etc. for now)
- */
- int cnt;
+ /* Reference count the base context usage */
+ struct kref kref;
+
/* Device context index */
unsigned ctxt;
/*
@@ -1291,7 +1289,8 @@ struct hfi1_ctxtdata *hfi1_create_ctxtda
void hfi1_init_pportdata(struct pci_dev *pdev, struct hfi1_pportdata *ppd,
struct hfi1_devdata *dd, u8 hw_pidx, u8 port);
void hfi1_free_ctxtdata(struct hfi1_devdata *dd, struct hfi1_ctxtdata *rcd);
-
+int hfi1_rcd_put(struct hfi1_ctxtdata *rcd);
+void hfi1_rcd_get(struct hfi1_ctxtdata *rcd);
int handle_receive_interrupt(struct hfi1_ctxtdata *rcd, int thread);
int handle_receive_interrupt_nodma_rtail(struct hfi1_ctxtdata *rcd, int thread);
int handle_receive_interrupt_dma_rtail(struct hfi1_ctxtdata *rcd, int thread);
--- a/drivers/infiniband/hw/hfi1/init.c
+++ b/drivers/infiniband/hw/hfi1/init.c
@@ -191,16 +191,46 @@ int hfi1_create_ctxts(struct hfi1_devdat
nomem:
ret = -ENOMEM;
- if (dd->rcd) {
- for (i = 0; i < dd->num_rcv_contexts; ++i)
- hfi1_free_ctxtdata(dd, dd->rcd[i]);
- }
+ for (i = 0; dd->rcd && i < dd->first_dyn_alloc_ctxt; ++i)
+ hfi1_rcd_put(dd->rcd[i]);
+
+ /* All the contexts should be freed, free the array */
kfree(dd->rcd);
dd->rcd = NULL;
return ret;
}
/*
+ * Helper routines for the receive context reference count (rcd and uctxt)
+ */
+static void hfi1_rcd_init(struct hfi1_ctxtdata *rcd)
+{
+ kref_init(&rcd->kref);
+}
+
+static void hfi1_rcd_free(struct kref *kref)
+{
+ struct hfi1_ctxtdata *rcd =
+ container_of(kref, struct hfi1_ctxtdata, kref);
+
+ hfi1_free_ctxtdata(rcd->dd, rcd);
+ kfree(rcd);
+}
+
+int hfi1_rcd_put(struct hfi1_ctxtdata *rcd)
+{
+ if (rcd)
+ return kref_put(&rcd->kref, hfi1_rcd_free);
+
+ return 0;
+}
+
+void hfi1_rcd_get(struct hfi1_ctxtdata *rcd)
+{
+ kref_get(&rcd->kref);
+}
+
+/*
* Common code for user and kernel context setup.
*/
struct hfi1_ctxtdata *hfi1_create_ctxtdata(struct hfi1_pportdata *ppd, u32 ctxt,
@@ -332,6 +362,8 @@ struct hfi1_ctxtdata *hfi1_create_ctxtda
if (!rcd->opstats)
goto bail;
}
+
+ hfi1_rcd_init(rcd);
}
return rcd;
bail:
@@ -931,14 +963,11 @@ static void shutdown_device(struct hfi1_
* @rcd: the ctxtdata structure
*
* free up any allocated data for a context
- * This should not touch anything that would affect a simultaneous
- * re-allocation of context data, because it is called after hfi1_mutex
- * is released (and can be called from reinit as well).
* It should never change any chip state, or global driver state.
*/
void hfi1_free_ctxtdata(struct hfi1_devdata *dd, struct hfi1_ctxtdata *rcd)
{
- unsigned e;
+ u32 e;
if (!rcd)
return;
@@ -957,6 +986,7 @@ void hfi1_free_ctxtdata(struct hfi1_devd
/* all the RcvArray entries should have been cleared by now */
kfree(rcd->egrbufs.rcvtids);
+ rcd->egrbufs.rcvtids = NULL;
for (e = 0; e < rcd->egrbufs.alloced; e++) {
if (rcd->egrbufs.buffers[e].dma)
@@ -966,13 +996,21 @@ void hfi1_free_ctxtdata(struct hfi1_devd
rcd->egrbufs.buffers[e].dma);
}
kfree(rcd->egrbufs.buffers);
+ rcd->egrbufs.alloced = 0;
+ rcd->egrbufs.buffers = NULL;
sc_free(rcd->sc);
+ rcd->sc = NULL;
+
vfree(rcd->subctxt_uregbase);
vfree(rcd->subctxt_rcvegrbuf);
vfree(rcd->subctxt_rcvhdr_base);
kfree(rcd->opstats);
- kfree(rcd);
+
+ rcd->subctxt_uregbase = NULL;
+ rcd->subctxt_rcvegrbuf = NULL;
+ rcd->subctxt_rcvhdr_base = NULL;
+ rcd->opstats = NULL;
}
/*
@@ -1366,7 +1404,7 @@ static void cleanup_device_data(struct h
tmp[ctxt] = NULL; /* debugging paranoia */
if (rcd) {
hfi1_clear_tids(rcd);
- hfi1_free_ctxtdata(dd, rcd);
+ hfi1_rcd_put(rcd);
}
}
kfree(tmp);
--- a/drivers/infiniband/hw/hfi1/vnic_main.c
+++ b/drivers/infiniband/hw/hfi1/vnic_main.c
@@ -156,11 +156,11 @@ static int allocate_vnic_ctxt(struct hfi
return ret;
bail:
/*
- * hfi1_free_ctxtdata() also releases send_context
- * structure if uctxt->sc is not null
+ * hfi1_rcd_put() will call hfi1_free_ctxtdata(), which will
+ * release send_context structure if uctxt->sc is not null
*/
dd->rcd[uctxt->ctxt] = NULL;
- hfi1_free_ctxtdata(dd, uctxt);
+ hfi1_rcd_put(uctxt);
dd_dev_dbg(dd, "vnic allocation failed. rc %d\n", ret);
return ret;
}
@@ -208,7 +208,7 @@ static void deallocate_vnic_ctxt(struct
hfi1_clear_ctxt_pkey(dd, uctxt);
hfi1_stats.sps_ctxts--;
- hfi1_free_ctxtdata(dd, uctxt);
+ hfi1_rcd_put(uctxt);
}
void hfi1_vnic_setup(struct hfi1_devdata *dd)
@@ -751,6 +751,7 @@ static int hfi1_vnic_init(struct hfi1_vn
rc = hfi1_vnic_allot_ctxt(dd, &dd->vnic.ctxt[i]);
if (rc)
break;
+ hfi1_rcd_get(dd->vnic.ctxt[i]);
dd->vnic.ctxt[i]->vnic_q_idx = i;
}
@@ -762,6 +763,7 @@ static int hfi1_vnic_init(struct hfi1_vn
*/
while (i-- > dd->vnic.num_ctxt) {
deallocate_vnic_ctxt(dd, dd->vnic.ctxt[i]);
+ hfi1_rcd_put(dd->vnic.ctxt[i]);
dd->vnic.ctxt[i] = NULL;
}
goto alloc_fail;
@@ -791,6 +793,7 @@ static void hfi1_vnic_deinit(struct hfi1
if (--dd->vnic.num_vports == 0) {
for (i = 0; i < dd->vnic.num_ctxt; i++) {
deallocate_vnic_ctxt(dd, dd->vnic.ctxt[i]);
+ hfi1_rcd_put(dd->vnic.ctxt[i]);
dd->vnic.ctxt[i] = NULL;
}
hfi1_deinit_vnic_rsm(dd);