linux-kernel - [PATCH 5.11 109/254] soc: ti: omap-prm: Fix occasional abort on reset deassert for dra7 iva

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, 29 Mar 2021 09:57:05 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Yongqin Liu <yongqin.liu@...aro.org>,
        Tony Lindgren <tony@...mide.com>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.11 109/254] soc: ti: omap-prm: Fix occasional abort on reset deassert for dra7 iva

From: Tony Lindgren <tony@...mide.com>

[ Upstream commit effe89e40037038db7711bdab5d3401fe297d72c ]

On reset deassert, we must wait a bit after the rstst bit change before
we allow clockdomain autoidle again. Otherwise we get the following oops
sometimes on dra7 with iva:

Unhandled fault: imprecise external abort (0x1406) at 0x00000000
44000000.ocp:L3 Standard Error: MASTER MPU TARGET IVA_CONFIG (Read Link):
At Address: 0x0005A410 : Data Access in User mode during Functional access
Internal error: : 1406 [#1] SMP ARM
...
(sysc_write_sysconfig) from [<c0782cb0>] (sysc_enable_module+0xcc/0x260)
(sysc_enable_module) from [<c0782f0c>] (sysc_runtime_resume+0xc8/0x174)
(sysc_runtime_resume) from [<c0a3e1ac>] (genpd_runtime_resume+0x94/0x224)
(genpd_runtime_resume) from [<c0a33f0c>] (__rpm_callback+0xd8/0x180)

It is unclear what all devices this might affect, but presumably other
devices with the rstst bit too can be affected. So let's just enable the
delay for all the devices with rstst bit for now. Later on we may want to
limit the list to the know affected devices if needed.

Fixes: d30cd83f6853 ("soc: ti: omap-prm: add support for denying idle for reset clockdomain")
Reported-by: Yongqin Liu <yongqin.liu@...aro.org>
Signed-off-by: Tony Lindgren <tony@...mide.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/soc/ti/omap_prm.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/soc/ti/omap_prm.c b/drivers/soc/ti/omap_prm.c
index 17ea6a74a988..51143a68a889 100644
--- a/drivers/soc/ti/omap_prm.c
+++ b/drivers/soc/ti/omap_prm.c
@@ -830,8 +830,12 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev,
 		       reset->prm->data->name, id);

 exit:
-	if (reset->clkdm)
+	if (reset->clkdm) {
+		/* At least dra7 iva needs a delay before clkdm idle */
+		if (has_rstst)
+			udelay(1);
 		pdata->clkdm_allow_idle(reset->clkdm);
+	}

 	return ret;
 }
-- 
2.30.1