linux-kernel - [PATCH AUTOSEL 4.19 32/60] usb: xhci: omit duplicate actions when suspending a runtime suspended host.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 26 Oct 2020 20:03:47 -0400
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Peter Chen <peter.chen@....com>, Jun Li <jun.li@....com>,
        Mathias Nyman <mathias.nyman@...ux.intel.com>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Sasha Levin <sashal@...nel.org>, linux-usb@...r.kernel.org
Subject: [PATCH AUTOSEL 4.19 32/60] usb: xhci: omit duplicate actions when suspending a runtime suspended host.

From: Peter Chen <peter.chen@....com>

[ Upstream commit 18a367e8947d72dd91b6fc401e88a2952c6363f7 ]

If the xhci-plat.c is the platform driver, after the runtime pm is
enabled, the xhci_suspend is called if nothing is connected on
the port. When the system goes to suspend, it will call xhci_suspend again
if USB wakeup is enabled.

Since the runtime suspend wakeup setting is not always the same as
system suspend wakeup setting, eg, at runtime suspend we always need
wakeup if the controller is in low power mode; but at system suspend,
we may not need wakeup. So, we move the judgement after changing
wakeup setting.

[commit message rewording -Mathias]

Reviewed-by: Jun Li <jun.li@....com>
Signed-off-by: Peter Chen <peter.chen@....com>
Signed-off-by: Mathias Nyman <mathias.nyman@...ux.intel.com>
Link: https://lore.kernel.org/r/20200918131752.16488-8-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/usb/host/xhci.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 6f976c4cccdae..0348ea899d062 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -972,12 +972,15 @@ int xhci_suspend(struct xhci_hcd *xhci, bool do_wakeup)
 			xhci->shared_hcd->state != HC_STATE_SUSPENDED)
 		return -EINVAL;
 
-	xhci_dbc_suspend(xhci);
-
 	/* Clear root port wake on bits if wakeup not allowed. */
 	if (!do_wakeup)
 		xhci_disable_port_wake_on_bits(xhci);
 
+	if (!HCD_HW_ACCESSIBLE(hcd))
+		return 0;
+
+	xhci_dbc_suspend(xhci);
+
 	/* Don't poll the roothubs on bus suspend. */
 	xhci_dbg(xhci, "%s: stopping port polling.\n", __func__);
 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
-- 
2.25.1