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 PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Thu, 28 Oct 2021 17:30:54 -0700 From: Guenter Roeck <linux@...ck-us.net> To: Sam Protsenko <semen.protsenko@...aro.org>, Wim Van Sebroeck <wim@...ux-watchdog.org>, Rob Herring <robh+dt@...nel.org>, Krzysztof Kozlowski <krzysztof.kozlowski@...onical.com> Cc: linux-watchdog@...r.kernel.org, devicetree@...r.kernel.org, linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org, linux-samsung-soc@...r.kernel.org Subject: Re: [PATCH 7/7] watchdog: s3c2410: Let kernel kick watchdog On 10/28/21 11:35 AM, Sam Protsenko wrote: > When "tmr_atboot" module param is set, the watchdog is started in > driver's probe. In that case, also set WDOG_HW_RUNNING bit to let > watchdog core driver know it's running. This way wathcdog core can kick > the watchdog for us (if CONFIG_WATCHDOG_HANDLE_BOOT_ENABLED option is > enabled), until user space takes control. > > Signed-off-by: Sam Protsenko <semen.protsenko@...aro.org> > --- > drivers/watchdog/s3c2410_wdt.c | 26 +++++++++++++++----------- > 1 file changed, 15 insertions(+), 11 deletions(-) > > diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c > index ca082b1226e3..9af014ff1468 100644 > --- a/drivers/watchdog/s3c2410_wdt.c > +++ b/drivers/watchdog/s3c2410_wdt.c > @@ -732,6 +732,21 @@ static int s3c2410wdt_probe(struct platform_device *pdev) > wdt->wdt_device.bootstatus = s3c2410wdt_get_bootstatus(wdt); > wdt->wdt_device.parent = dev; > > + /* > + * If "tmr_atboot" param is non-zero, start the watchdog right now. Also > + * set WDOG_HW_RUNNING bit, so that watchdog core can kick the watchdog. > + * > + * If we're not enabling the watchdog, then ensure it is disabled if it > + * has been left running from the bootloader or other source. > + */ > + if (tmr_atboot && started == 0) { > + dev_info(dev, "starting watchdog timer\n"); > + s3c2410wdt_start(&wdt->wdt_device); > + set_bit(WDOG_HW_RUNNING, &wdt->wdt_device.status); > + } else if (!tmr_atboot) { > + s3c2410wdt_stop(&wdt->wdt_device); > + } > + This doesn't cover the case where the watchdog is already enabled by the BIOS. In that case, WDOG_HW_RUNNING won't be set, and the watchdog will time out if the userspace handler is not loaded fast enough. The code should consistently set WDOG_HW_RUNNING if the watchdog is running. Guenter > ret = watchdog_register_device(&wdt->wdt_device); > if (ret) > goto err_cpufreq; > @@ -740,17 +755,6 @@ static int s3c2410wdt_probe(struct platform_device *pdev) > if (ret < 0) > goto err_unregister; > > - if (tmr_atboot && started == 0) { > - dev_info(dev, "starting watchdog timer\n"); > - s3c2410wdt_start(&wdt->wdt_device); > - } else if (!tmr_atboot) { > - /* if we're not enabling the watchdog, then ensure it is > - * disabled if it has been left running from the bootloader > - * or other source */ > - > - s3c2410wdt_stop(&wdt->wdt_device); > - } > - > platform_set_drvdata(pdev, wdt); > > /* print out a statement of readiness */ >
Powered by blists - more mailing lists