| Message ID | 20180122150748.1742-1-andrew.smirnov@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Jan 22, 2018 at 07:07:47AM -0800, Andrey Smirnov wrote: > Platform device core assumes the ownership of dev.platform_data as > well as that it is dynamically allocated and it will try to kfree it > as a part of platform_device_release(). Change the code to pass > kzalloc'ed chunk of memory instead of a pointer to a static memory to > avoid causing a BUG() when calling platform_device_put(). > > The problem can be reproduced by artificially enabling the error path > of platform_device_add() call (around line 357). > > Note that this change also allows us to constify imx7_pgc_domains, > since we no longer need to be able to modify it. > > Cc: Shawn Guo <shawnguo@kernel.org> > Cc: Stefan Agner <stefan@agner.ch> > Cc: Lucas Stach <l.stach@pengutronix.de> > Cc: linux-arm-kernel@lists.infradead.org > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com> Applied both, thanks.
On Thu, Feb 08, 2018 at 02:47:10PM +0800, Shawn Guo wrote: > On Mon, Jan 22, 2018 at 07:07:47AM -0800, Andrey Smirnov wrote: > > Platform device core assumes the ownership of dev.platform_data as > > well as that it is dynamically allocated and it will try to kfree it > > as a part of platform_device_release(). Change the code to pass > > kzalloc'ed chunk of memory instead of a pointer to a static memory to > > avoid causing a BUG() when calling platform_device_put(). > > > > The problem can be reproduced by artificially enabling the error path > > of platform_device_add() call (around line 357). > > > > Note that this change also allows us to constify imx7_pgc_domains, > > since we no longer need to be able to modify it. > > > > Cc: Shawn Guo <shawnguo@kernel.org> > > Cc: Stefan Agner <stefan@agner.ch> > > Cc: Lucas Stach <l.stach@pengutronix.de> > > Cc: linux-arm-kernel@lists.infradead.org > > Cc: linux-kernel@vger.kernel.org > > Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com> > > Applied both, thanks. I decided to drop these two patches. Triggered by Fabio's patch on top of you changes, I just took another look at them, and found that platform_device_add_data() can help us do the same thing in a nicer way. Shawn [1] https://patchwork.kernel.org/patch/10274969/
On Wed, Mar 14, 2018 at 8:08 PM, Shawn Guo <shawnguo@kernel.org> wrote: > On Thu, Feb 08, 2018 at 02:47:10PM +0800, Shawn Guo wrote: >> On Mon, Jan 22, 2018 at 07:07:47AM -0800, Andrey Smirnov wrote: >> > Platform device core assumes the ownership of dev.platform_data as >> > well as that it is dynamically allocated and it will try to kfree it >> > as a part of platform_device_release(). Change the code to pass >> > kzalloc'ed chunk of memory instead of a pointer to a static memory to >> > avoid causing a BUG() when calling platform_device_put(). >> > >> > The problem can be reproduced by artificially enabling the error path >> > of platform_device_add() call (around line 357). >> > >> > Note that this change also allows us to constify imx7_pgc_domains, >> > since we no longer need to be able to modify it. >> > >> > Cc: Shawn Guo <shawnguo@kernel.org> >> > Cc: Stefan Agner <stefan@agner.ch> >> > Cc: Lucas Stach <l.stach@pengutronix.de> >> > Cc: linux-arm-kernel@lists.infradead.org >> > Cc: linux-kernel@vger.kernel.org >> > Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com> >> >> Applied both, thanks. > > I decided to drop these two patches. Triggered by Fabio's patch on top > of you changes, I just took another look at them, and found that > platform_device_add_data() can help us do the same thing in a nicer way. > Shawn: I am slightly confused by your phrasing. Are you: a) saying that you dropped my patches in favor of your own that use platform_device_add_data() or b) asking me to convert my patches to use platform_device_add_data()? Just trying to figure out if any action on my part is necessary. Thanks, Andrey Smirnov
On Thu, Mar 15, 2018 at 06:00:06AM -0700, Andrey Smirnov wrote: > I am slightly confused by your phrasing. Are you: > > a) saying that you dropped my patches in favor of your own that use > platform_device_add_data() > > or > > b) asking me to convert my patches to use platform_device_add_data()? > > Just trying to figure out if any action on my part is necessary. Sorry for the blur. I'm asking you to repost your patches with using platform_device_add_data(). In other word, that's b). Shawn
On Thu, Mar 15, 2018 at 6:52 AM, Shawn Guo <shawnguo@kernel.org> wrote: > On Thu, Mar 15, 2018 at 06:00:06AM -0700, Andrey Smirnov wrote: >> I am slightly confused by your phrasing. Are you: >> >> a) saying that you dropped my patches in favor of your own that use >> platform_device_add_data() >> >> or >> >> b) asking me to convert my patches to use platform_device_add_data()? >> >> Just trying to figure out if any action on my part is necessary. > > Sorry for the blur. I'm asking you to repost your patches with using > platform_device_add_data(). In other word, that's b). OK, cool, will do. Thanks, Andrey Smirnov
diff --git a/drivers/soc/imx/gpcv2.c b/drivers/soc/imx/gpcv2.c index afc7ecc3c187..9947598ec4b5 100644 --- a/drivers/soc/imx/gpcv2.c +++ b/drivers/soc/imx/gpcv2.c @@ -18,6 +18,7 @@ #include <linux/pm_domain.h> #include <linux/regmap.h> #include <linux/regulator/consumer.h> +#include <linux/slab.h> #include <dt-bindings/power/imx7-power.h> #define GPC_LPCR_A7_BSC 0x000 @@ -155,7 +156,7 @@ static int imx7_gpc_pu_pgc_sw_pdn_req(struct generic_pm_domain *genpd) return imx7_gpc_pu_pgc_sw_pxx_req(genpd, false); } -static struct imx7_pgc_domain imx7_pgc_domains[] = { +static const struct imx7_pgc_domain imx7_pgc_domains[] = { [IMX7_POWER_DOMAIN_MIPI_PHY] = { .genpd = { .name = "mipi-phy", @@ -321,7 +322,14 @@ static int imx_gpcv2_probe(struct platform_device *pdev) continue; } - domain = &imx7_pgc_domains[domain_index]; + domain = kmalloc(sizeof(*domain), GFP_KERNEL); + if (!domain) { + of_node_put(np); + return -ENOMEM; + } + memcpy(domain, &imx7_pgc_domains[domain_index], + sizeof(*domain)); + domain->regmap = regmap; domain->genpd.power_on = imx7_gpc_pu_pgc_sw_pup_req; domain->genpd.power_off = imx7_gpc_pu_pgc_sw_pdn_req; @@ -330,6 +338,7 @@ static int imx_gpcv2_probe(struct platform_device *pdev) domain_index); if (!pd_pdev) { dev_err(dev, "Failed to allocate platform device\n"); + kfree(domain); of_node_put(np); return -ENOMEM; }
Platform device core assumes the ownership of dev.platform_data as well as that it is dynamically allocated and it will try to kfree it as a part of platform_device_release(). Change the code to pass kzalloc'ed chunk of memory instead of a pointer to a static memory to avoid causing a BUG() when calling platform_device_put(). The problem can be reproduced by artificially enabling the error path of platform_device_add() call (around line 357). Note that this change also allows us to constify imx7_pgc_domains, since we no longer need to be able to modify it. Cc: Shawn Guo <shawnguo@kernel.org> Cc: Stefan Agner <stefan@agner.ch> Cc: Lucas Stach <l.stach@pengutronix.de> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com> --- Changes since [v1]: - Replaced devm_kzalloc() with devm_kmalloc() as per suggestion from Stefan [1] lkml.kernel.org/r/20180110161608.13015-1-andrew.smirnov@gmail.com drivers/soc/imx/gpcv2.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-)