| Message ID | 20170802195129.20442-1-stefan@agner.ch (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Aug 02, 2017 at 12:51:29PM -0700, Stefan Agner wrote: > If a regulator requests a deferred probe, the power domain gets > initialized twice. This leads to a list double add (without > list debugging the kernel hangs due to the double add later): > > WARNING: CPU: 0 PID: 19 at lib/list_debug.c:31 __list_add_valid+0xbc/0xc4 > list_add double add: new=c1229754, prev=c12383b4, next=c1229754. > > Initialize the power domain after we get the regulator. Also do > not print an error in case the regulator defers probing. > > Cc: Fabio Estevam <fabio.estevam@nxp.com> > Cc: Andrey Smirnov <andrew.smirnov@gmail.com> > Cc: linux-arm-kernel@lists.infradead.org > Cc: linux-kernel@vger.kernel.org > Fixes: 03aa12629fc4 ("soc: imx: Add GPCv2 power gating driver") > Signed-off-by: Stefan Agner <stefan@agner.ch> > --- > Hi Shawn, > > Since this leads to a Kernel hang in v4.13-rc3, can you get this > into v4.13 still? Sure. But before doing that, I would like to get an ACK from Andrey on this fix. Shawn
On Wed, Aug 2, 2017 at 12:51 PM, Stefan Agner <stefan@agner.ch> wrote: > If a regulator requests a deferred probe, the power domain gets > initialized twice. This leads to a list double add (without > list debugging the kernel hangs due to the double add later): > > WARNING: CPU: 0 PID: 19 at lib/list_debug.c:31 __list_add_valid+0xbc/0xc4 > list_add double add: new=c1229754, prev=c12383b4, next=c1229754. > > Initialize the power domain after we get the regulator. Also do > not print an error in case the regulator defers probing. > > Cc: Fabio Estevam <fabio.estevam@nxp.com> > Cc: Andrey Smirnov <andrew.smirnov@gmail.com> > Cc: linux-arm-kernel@lists.infradead.org > Cc: linux-kernel@vger.kernel.org > Fixes: 03aa12629fc4 ("soc: imx: Add GPCv2 power gating driver") > Signed-off-by: Stefan Agner <stefan@agner.ch> As the author of original bug: Acked-by: Andrey Smirnov <andrew.smirnov@gmail.com> I also went ahead and tested PCIe on my SabreSD with Intel Gigabit adapter, so Tested-by: Andrey Smirnov <andrew.smirnov@gmail.com> Thanks for debugging and fixing this! Andrey Smirnov
On Wed, Aug 02, 2017 at 12:51:29PM -0700, Stefan Agner wrote: > If a regulator requests a deferred probe, the power domain gets > initialized twice. This leads to a list double add (without > list debugging the kernel hangs due to the double add later): > > WARNING: CPU: 0 PID: 19 at lib/list_debug.c:31 __list_add_valid+0xbc/0xc4 > list_add double add: new=c1229754, prev=c12383b4, next=c1229754. > > Initialize the power domain after we get the regulator. Also do > not print an error in case the regulator defers probing. > > Cc: Fabio Estevam <fabio.estevam@nxp.com> > Cc: Andrey Smirnov <andrew.smirnov@gmail.com> > Cc: linux-arm-kernel@lists.infradead.org > Cc: linux-kernel@vger.kernel.org > Fixes: 03aa12629fc4 ("soc: imx: Add GPCv2 power gating driver") > Signed-off-by: Stefan Agner <stefan@agner.ch> Applied, thanks.
Hi Shawn, On 2017-08-04 20:13, Shawn Guo wrote: > On Wed, Aug 02, 2017 at 12:51:29PM -0700, Stefan Agner wrote: >> If a regulator requests a deferred probe, the power domain gets >> initialized twice. This leads to a list double add (without >> list debugging the kernel hangs due to the double add later): >> >> WARNING: CPU: 0 PID: 19 at lib/list_debug.c:31 __list_add_valid+0xbc/0xc4 >> list_add double add: new=c1229754, prev=c12383b4, next=c1229754. >> >> Initialize the power domain after we get the regulator. Also do >> not print an error in case the regulator defers probing. >> >> Cc: Fabio Estevam <fabio.estevam@nxp.com> >> Cc: Andrey Smirnov <andrew.smirnov@gmail.com> >> Cc: linux-arm-kernel@lists.infradead.org >> Cc: linux-kernel@vger.kernel.org >> Fixes: 03aa12629fc4 ("soc: imx: Add GPCv2 power gating driver") >> Signed-off-by: Stefan Agner <stefan@agner.ch> > > Applied, thanks. As of 4.13-rc5 this did not make it upstream yet, I guess still on its way? -- Stefan
On Sun, Aug 13, 2017 at 10:12:13PM -0700, Stefan Agner wrote: > Hi Shawn, > > On 2017-08-04 20:13, Shawn Guo wrote: > > On Wed, Aug 02, 2017 at 12:51:29PM -0700, Stefan Agner wrote: > >> If a regulator requests a deferred probe, the power domain gets > >> initialized twice. This leads to a list double add (without > >> list debugging the kernel hangs due to the double add later): > >> > >> WARNING: CPU: 0 PID: 19 at lib/list_debug.c:31 __list_add_valid+0xbc/0xc4 > >> list_add double add: new=c1229754, prev=c12383b4, next=c1229754. > >> > >> Initialize the power domain after we get the regulator. Also do > >> not print an error in case the regulator defers probing. > >> > >> Cc: Fabio Estevam <fabio.estevam@nxp.com> > >> Cc: Andrey Smirnov <andrew.smirnov@gmail.com> > >> Cc: linux-arm-kernel@lists.infradead.org > >> Cc: linux-kernel@vger.kernel.org > >> Fixes: 03aa12629fc4 ("soc: imx: Add GPCv2 power gating driver") > >> Signed-off-by: Stefan Agner <stefan@agner.ch> > > > > Applied, thanks. > > As of 4.13-rc5 this did not make it upstream yet, I guess still on its > way? Yes, Stefan. It's on the way to arm-soc [1], but not yet responded. Shawn [1] https://www.spinics.net/lists/arm-kernel/msg598634.html
On Mon, Aug 14, 2017 at 7:35 AM, Shawn Guo <shawnguo@kernel.org> wrote: > On Sun, Aug 13, 2017 at 10:12:13PM -0700, Stefan Agner wrote: >> Hi Shawn, >> >> On 2017-08-04 20:13, Shawn Guo wrote: >> > On Wed, Aug 02, 2017 at 12:51:29PM -0700, Stefan Agner wrote: >> >> If a regulator requests a deferred probe, the power domain gets >> >> initialized twice. This leads to a list double add (without >> >> list debugging the kernel hangs due to the double add later): >> >> >> >> WARNING: CPU: 0 PID: 19 at lib/list_debug.c:31 __list_add_valid+0xbc/0xc4 >> >> list_add double add: new=c1229754, prev=c12383b4, next=c1229754. >> >> >> >> Initialize the power domain after we get the regulator. Also do >> >> not print an error in case the regulator defers probing. >> >> >> >> Cc: Fabio Estevam <fabio.estevam@nxp.com> >> >> Cc: Andrey Smirnov <andrew.smirnov@gmail.com> >> >> Cc: linux-arm-kernel@lists.infradead.org >> >> Cc: linux-kernel@vger.kernel.org >> >> Fixes: 03aa12629fc4 ("soc: imx: Add GPCv2 power gating driver") >> >> Signed-off-by: Stefan Agner <stefan@agner.ch> >> > >> > Applied, thanks. >> >> As of 4.13-rc5 this did not make it upstream yet, I guess still on its >> way? > > Yes, Stefan. It's on the way to arm-soc [1], but not yet responded. > > Shawn > > [1] https://www.spinics.net/lists/arm-kernel/msg598634.html Merged into arm-soc now with Shawn's pull request. Arnd
diff --git a/drivers/soc/imx/gpcv2.c b/drivers/soc/imx/gpcv2.c index 3039072911a5..afc7ecc3c187 100644 --- a/drivers/soc/imx/gpcv2.c +++ b/drivers/soc/imx/gpcv2.c @@ -200,16 +200,11 @@ static int imx7_pgc_domain_probe(struct platform_device *pdev) domain->dev = &pdev->dev; - ret = pm_genpd_init(&domain->genpd, NULL, true); - if (ret) { - dev_err(domain->dev, "Failed to init power domain\n"); - return ret; - } - domain->regulator = devm_regulator_get_optional(domain->dev, "power"); if (IS_ERR(domain->regulator)) { if (PTR_ERR(domain->regulator) != -ENODEV) { - dev_err(domain->dev, "Failed to get domain's regulator\n"); + if (PTR_ERR(domain->regulator) != -EPROBE_DEFER) + dev_err(domain->dev, "Failed to get domain's regulator\n"); return PTR_ERR(domain->regulator); } } else { @@ -217,6 +212,12 @@ static int imx7_pgc_domain_probe(struct platform_device *pdev) domain->voltage, domain->voltage); } + ret = pm_genpd_init(&domain->genpd, NULL, true); + if (ret) { + dev_err(domain->dev, "Failed to init power domain\n"); + return ret; + } + ret = of_genpd_add_provider_simple(domain->dev->of_node, &domain->genpd); if (ret) {
If a regulator requests a deferred probe, the power domain gets initialized twice. This leads to a list double add (without list debugging the kernel hangs due to the double add later): WARNING: CPU: 0 PID: 19 at lib/list_debug.c:31 __list_add_valid+0xbc/0xc4 list_add double add: new=c1229754, prev=c12383b4, next=c1229754. Initialize the power domain after we get the regulator. Also do not print an error in case the regulator defers probing. Cc: Fabio Estevam <fabio.estevam@nxp.com> Cc: Andrey Smirnov <andrew.smirnov@gmail.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Fixes: 03aa12629fc4 ("soc: imx: Add GPCv2 power gating driver") Signed-off-by: Stefan Agner <stefan@agner.ch> --- Hi Shawn, Since this leads to a Kernel hang in v4.13-rc3, can you get this into v4.13 still? -- Stefan drivers/soc/imx/gpcv2.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-)