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Date: Wed, 2 Jul 2014 04:34:49 +0200
From: "Luis R. Rodriguez" <mcgrof@...e.com>
To: Ming Lei <ming.lei@...onical.com>
Cc: Takashi Iwai <tiwai@...e.de>,
"Luis R. Rodriguez" <mcgrof@...not-panic.com>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
Tom Gundersen <teg@...m.no>,
Abhay Salunke <Abhay_Salunke@...l.com>,
Stefan Roese <sr@...x.de>, Arnd Bergmann <arnd@...db.de>,
Kay Sievers <kay@...y.org>
Subject: Re: [PATCH] firmware loader: inform direct failure when udev
loader is disabled
On Wed, Jul 02, 2014 at 09:51:36AM +0800, Ming Lei wrote:
> On Wed, Jul 2, 2014 at 9:01 AM, Luis R. Rodriguez <mcgrof@...e.com> wrote:
> > On Tue, Jul 01, 2014 at 11:22:07AM +0200, Takashi Iwai wrote:
> >> At Tue, 1 Jul 2014 11:54:24 +0800,
> >> Ming Lei wrote:
> >> >
> >> > On Tue, Jul 1, 2014 at 7:30 AM, Luis R. Rodriguez
> >> > <mcgrof@...not-panic.com> wrote:
> >> > > From: "Luis R. Rodriguez" <mcgrof@...e.com>
> >> > >
> >> > > Now that the udev firmware loader is optional request_firmware()
> >> > > will not provide any information on the kernel ring buffer if
> >> > > direct firmware loading failed and udev firmware loading is disabled.
> >> > > If no information is needed request_firmware_direct() should be used
> >> > > for optional firmware, at which point drivers can take on the onus
> >> > > over informing of any failures, if udev firmware loading is disabled
> >> > > though we should at the very least provide some sort of information
> >> > > as when the udev loader was enabled by default back in the days.
> >> > >
> >> > > With this change with a simple firmware load test module [0]:
> >> > >
> >> > > Example output without FW_LOADER_USER_HELPER_FALLBACK
> >> > >
> >> > > platform fake-dev.0: Direct firmware load for fake.bin failed with error -2
> >> > >
> >> > > Example without FW_LOADER_USER_HELPER_FALLBACK
> >> > >
> >> > > platform fake-dev.0: Direct firmware load for fake.bin failed with error -2
> >> > > platform fake-dev.0: Falling back to user helper
> >> > >
> >> > > Without this change without FW_LOADER_USER_HELPER_FALLBACK we get no output
> >> > > logged upon failure.
> >> > >
> >> > > [0] https://github.com/mcgrof/fake-firmware-test.git
> >> > >
> >> > > Cc: Tom Gundersen <teg@...m.no>
> >> > > Cc: Ming Lei <ming.lei@...onical.com>
> >> > > Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
> >> > > Cc: Abhay Salunke <Abhay_Salunke@...l.com>
> >> > > Cc: Stefan Roese <sr@...x.de>
> >> > > Cc: Arnd Bergmann <arnd@...db.de>
> >> > > Cc: Kay Sievers <kay@...y.org>
> >> > > Cc: Takashi Iwai <tiwai@...e.de>
> >> > > Signed-off-by: Luis R. Rodriguez <mcgrof@...e.com>
> >> > > ---
> >> > >
> >> > > drivers/base/firmware_class.c | 12 ++++++++----
> >> > > 1 file changed, 8 insertions(+), 4 deletions(-)
> >> > >
> >> > > diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
> >> > > index 46ea5f4..23274d8 100644
> >> > > --- a/drivers/base/firmware_class.c
> >> > > +++ b/drivers/base/firmware_class.c
> >> > > @@ -101,8 +101,10 @@ static inline long firmware_loading_timeout(void)
> >> > > #define FW_OPT_NOWAIT (1U << 1)
> >> > > #ifdef CONFIG_FW_LOADER_USER_HELPER
> >> > > #define FW_OPT_USERHELPER (1U << 2)
> >> > > +#define FW_OPT_FAIL_WARN 0
> >> > > #else
> >> > > #define FW_OPT_USERHELPER 0
> >> > > +#define FW_OPT_FAIL_WARN (1U << 3)
> >> > > #endif
> >> > > #ifdef CONFIG_FW_LOADER_USER_HELPER_FALLBACK
> >> > > #define FW_OPT_FALLBACK FW_OPT_USERHELPER
> >> > > @@ -1116,10 +1118,11 @@ _request_firmware(const struct firmware **firmware_p, const char *name,
> >> > >
> >> > > ret = fw_get_filesystem_firmware(device, fw->priv);
> >> > > if (ret) {
> >> > > - if (opt_flags & FW_OPT_USERHELPER) {
> >> > > + if (opt_flags & (FW_OPT_FAIL_WARN | FW_OPT_USERHELPER))
> >> > > dev_warn(device,
> >> > > - "Direct firmware load failed with error %d\n",
> >> > > - ret);
> >> > > + "Direct firmware load for %s failed with error %d\n",
> >> > > + name, ret);
> >> >
> >> > Maybe the warning can be always printed out since
> >> > (FW_OPT_FAIL_WARN | FW_OPT_USERHELPER) should be
> >> > always true.
> >>
> >> Yes, it'd be simpler. Let's reduce lines! :)
> >
> > Actually we don't want to warn when request_firmware_direct() is used right? That's really what
>
> Yes, that is for the CPU microcode update in which it is common to
> fail in direct loading, and x86 guys hate the warning.
I've extended use of request_firmware_direct() to drivers that also load
non-firmware but optional config files, EEPROM override, etc.
> > I meant to upkeep while adding a warning when _direct() is not used. So how about
> > this as an ammendment:
>
> Yes, the idea is right, and it is good to make request_firmware_direct()
> not depend on CONFIG_FW_LOADER_USER_HELPER, and with
> one FW_OPT_DIRECT_ONLY flag together it should work.
OK.
> > diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
> > index 23274d8..4f6adf3 100644
> > --- a/drivers/base/firmware_class.c
> > +++ b/drivers/base/firmware_class.c
> > @@ -66,13 +68,12 @@ static inline void release_firmware(const struct firmware *fw)
> > {
> > }
> >
> > -#endif
> > +static inline int request_firmware_direct(const struct firmware **fw,
> > + const char *name,
> > + struct device *device)
> > +{
> > + return -EINVAL;
> > +}
>
> You define two request_firmware_direct?
This is the negative of
#if defined(CONFIG_FW_LOADER) || (defined(CONFIG_FW_LOADER_MODULE) && defined(MODULE))
We have two also for request_firmware().
Will send out a v2.
Luis
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