This is a note to let you know that I've just added the patch titled
usb: xhci: check if 'requested segments' exceeds ERST capacity
to the 6.8-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
usb-xhci-check-if-requested-segments-exceeds-erst-ca.patch
and it can be found in the queue-6.8 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit d2b506d4c9b8db4e2bba4060da8f88fe28ed4cfc
Author: Niklas Neronin <niklas.neronin@xxxxxxxxxxxxxxx>
Date: Mon Apr 29 17:02:30 2024 +0300
usb: xhci: check if 'requested segments' exceeds ERST capacity
[ Upstream commit db4460b6ecf07574d580f01cd88054a62607068c ]
Check if requested segments ('segs' or 'ERST_DEFAULT_SEGS') exceeds the
maximum amount ERST supports.
When 'segs' is '0', 'ERST_DEFAULT_SEGS' is used instead. But both values
may not exceed ERST max.
Macro 'ERST_MAX_SEGS' is renamed to 'ERST_DEFAULT_SEGS'. The new name
better represents the macros, which is the number of Event Ring segments
to allocate, when the amount is not specified.
Additionally, rename and change xhci_create_secondary_interrupter()'s
argument 'int num_segs' to 'unsigned int segs'. This makes it the same
as its counter part in xhci_alloc_interrupter().
Fixes: c99b38c41234 ("xhci: add support to allocate several interrupters")
Signed-off-by: Niklas Neronin <niklas.neronin@xxxxxxxxxxxxxxx>
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240429140245.3955523-4-mathias.nyman@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 450adaca68eeb..2246bb0dea191 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -2280,24 +2280,24 @@ static int xhci_setup_port_arrays(struct xhci_hcd *xhci, gfp_t flags)
}
static struct xhci_interrupter *
-xhci_alloc_interrupter(struct xhci_hcd *xhci, int segs, gfp_t flags)
+xhci_alloc_interrupter(struct xhci_hcd *xhci, unsigned int segs, gfp_t flags)
{
struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
struct xhci_interrupter *ir;
- unsigned int num_segs = segs;
+ unsigned int max_segs;
int ret;
+ if (!segs)
+ segs = ERST_DEFAULT_SEGS;
+
+ max_segs = BIT(HCS_ERST_MAX(xhci->hcs_params2));
+ segs = min(segs, max_segs);
+
ir = kzalloc_node(sizeof(*ir), flags, dev_to_node(dev));
if (!ir)
return NULL;
- /* number of ring segments should be greater than 0 */
- if (segs <= 0)
- num_segs = min_t(unsigned int, 1 << HCS_ERST_MAX(xhci->hcs_params2),
- ERST_MAX_SEGS);
-
- ir->event_ring = xhci_ring_alloc(xhci, num_segs, 1, TYPE_EVENT, 0,
- flags);
+ ir->event_ring = xhci_ring_alloc(xhci, segs, 1, TYPE_EVENT, 0, flags);
if (!ir->event_ring) {
xhci_warn(xhci, "Failed to allocate interrupter event ring\n");
kfree(ir);
@@ -2355,7 +2355,7 @@ xhci_add_interrupter(struct xhci_hcd *xhci, struct xhci_interrupter *ir,
}
struct xhci_interrupter *
-xhci_create_secondary_interrupter(struct usb_hcd *hcd, int num_seg)
+xhci_create_secondary_interrupter(struct usb_hcd *hcd, unsigned int segs)
{
struct xhci_hcd *xhci = hcd_to_xhci(hcd);
struct xhci_interrupter *ir;
@@ -2365,7 +2365,7 @@ xhci_create_secondary_interrupter(struct usb_hcd *hcd, int num_seg)
if (!xhci->interrupters || xhci->max_interrupters <= 1)
return NULL;
- ir = xhci_alloc_interrupter(xhci, num_seg, GFP_KERNEL);
+ ir = xhci_alloc_interrupter(xhci, segs, GFP_KERNEL);
if (!ir)
return NULL;
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index bf05103aa68a0..a736b3cf366d3 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1649,8 +1649,8 @@ struct urb_priv {
struct xhci_td td[] __counted_by(num_tds);
};
-/* Reasonable limit for number of Event Ring segments (spec allows 32k) */
-#define ERST_MAX_SEGS 2
+/* Number of Event Ring segments to allocate, when amount is not specified. (spec allows 32k) */
+#define ERST_DEFAULT_SEGS 2
/* Poll every 60 seconds */
#define POLL_TIMEOUT 60
/* Stop endpoint command timeout (secs) for URB cancellation watchdog timer */
@@ -2088,7 +2088,7 @@ struct xhci_container_ctx *xhci_alloc_container_ctx(struct xhci_hcd *xhci,
void xhci_free_container_ctx(struct xhci_hcd *xhci,
struct xhci_container_ctx *ctx);
struct xhci_interrupter *
-xhci_create_secondary_interrupter(struct usb_hcd *hcd, int num_seg);
+xhci_create_secondary_interrupter(struct usb_hcd *hcd, unsigned int segs);
void xhci_remove_secondary_interrupter(struct usb_hcd
*hcd, struct xhci_interrupter *ir);
