[PATCH v3 0/4] Add request_firmware_direct() for microcode loader

[PATCH v3 0/4] Add request_firmware_direct() for microcode loader

[Takashi Iwai]

Hi,

this is a revised patch series to introduce request_firmware_direct()
helper for avoiding the lengthy udev issue on microcode loader.
The original problem was stated in Prarit's post:
   https://lkml.org/lkml/2013/10/28/221

In short, microcode loader probes non-existing firmware files (which
are cases with every new chip), and each probe takes 60 seconds,
resulting in too long time until completed.

This solution is simply avoiding the udev fallback in
request_firmware() explicitly for drivers like microcode.

Of course, this doesn't mean to throw away further optimizations like
Prarit's patch.  It can be implemented in parallel with this.


 [PATCH v3 1/4] firmware: Introduce request_firmware_direct()
 [PATCH v3 2/4] microcode: Use request_firmware_direct()
 [PATCH v3 3/4] firmware: Use bit flags instead of boolean combos
 [PATCH v3 4/4] firmware: Suppress fallback warnings when CONFIG_FW_LOADER_USER_HELPER=n

v1->v2: Rebased on linux-next, add a fix for a bogus warning message
v2->v3: Convert to bit flags, fix warning message differently


Greg, could you take these patches through your driver tree, as
most of fixes are about the firmware loader itself.


thanks,

Takashi

[PATCH v3 1/4] firmware: Introduce request_firmware_direct()

[Takashi Iwai]

When CONFIG_FW_LOADER_USER_HELPER is set, request_firmware() falls
back to the usermode helper for loading via udev when the direct
loading fails.  But the recent udev takes way too long timeout (60
seconds) for non-existing firmware.  This is unacceptable for the
drivers like microcode loader where they load firmwares optionally,
i.e. it's no error even if no requested file exists.

This patch provides a new helper function, request_firmware_direct().
It behaves as same as request_firmware() except for that it doesn't
fall back to usermode helper but returns an error immediately if the
f/w can't be loaded directly in kernel.

Without CONFIG_FW_LOADER_USER_HELPER=y, request_firmware_direct() is
just an alias of request_firmware(), due to obvious reason.

Tested-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Ming Lei <ming.lei@canonical.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
 drivers/base/firmware_class.c | 41 ++++++++++++++++++++++++++++++++++-------
 include/linux/firmware.h      |  7 +++++++
 2 files changed, 41 insertions(+), 7 deletions(-)

diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index eb8fb94ae2c5..1af03648daf8 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -1061,7 +1061,7 @@ static int assign_firmware_buf(struct firmware *fw, struct device *device,
 /* called from request_firmware() and request_firmware_work_func() */
 static int
 _request_firmware(const struct firmware **firmware_p, const char *name,
-		  struct device *device, bool uevent, bool nowait)
+		  struct device *device, bool uevent, bool nowait, bool fallback)
 {
 	struct firmware *fw;
 	long timeout;
@@ -1095,11 +1095,14 @@ _request_firmware(const struct firmware **firmware_p, const char *name,
 
 	ret = fw_get_filesystem_firmware(device, fw->priv);
 	if (ret) {
-		dev_warn(device, "Direct firmware load failed with error %d\n",
-			 ret);
-		dev_warn(device, "Falling back to user helper\n");
-		ret = fw_load_from_user_helper(fw, name, device,
+		if (fallback) {
+			dev_warn(device,
+				 "Direct firmware load failed with error %d\n",
+				 ret);
+			dev_warn(device, "Falling back to user helper\n");
+			ret = fw_load_from_user_helper(fw, name, device,
 					       uevent, nowait, timeout);
+		}
 	}
 
 	/* don't cache firmware handled without uevent */
@@ -1146,12 +1149,36 @@ request_firmware(const struct firmware **firmware_p, const char *name,
 
 	/* Need to pin this module until return */
 	__module_get(THIS_MODULE);
-	ret = _request_firmware(firmware_p, name, device, true, false);
+	ret = _request_firmware(firmware_p, name, device, true, false, true);
 	module_put(THIS_MODULE);
 	return ret;
 }
 EXPORT_SYMBOL(request_firmware);
 
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+/**
+ * request_firmware: - load firmware directly without usermode helper
+ * @firmware_p: pointer to firmware image
+ * @name: name of firmware file
+ * @device: device for which firmware is being loaded
+ *
+ * This function works pretty much like request_firmware(), but this doesn't
+ * fall back to usermode helper even if the firmware couldn't be loaded
+ * directly from fs.  Hence it's useful for loading optional firmwares, which
+ * aren't always present, without extra long timeouts of udev.
+ **/
+int request_firmware_direct(const struct firmware **firmware_p,
+			    const char *name, struct device *device)
+{
+	int ret;
+	__module_get(THIS_MODULE);
+	ret = _request_firmware(firmware_p, name, device, true, false, false);
+	module_put(THIS_MODULE);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(request_firmware_direct);
+#endif
+
 /**
  * release_firmware: - release the resource associated with a firmware image
  * @fw: firmware resource to release
@@ -1185,7 +1212,7 @@ static void request_firmware_work_func(struct work_struct *work)
 	fw_work = container_of(work, struct firmware_work, work);
 
 	_request_firmware(&fw, fw_work->name, fw_work->device,
-			  fw_work->uevent, true);
+			  fw_work->uevent, true, true);
 	fw_work->cont(fw, fw_work->context);
 	put_device(fw_work->device); /* taken in request_firmware_nowait() */
 
diff --git a/include/linux/firmware.h b/include/linux/firmware.h
index e154c1005cd1..59529330efd6 100644
--- a/include/linux/firmware.h
+++ b/include/linux/firmware.h
@@ -68,4 +68,11 @@ static inline void release_firmware(const struct firmware *fw)
 
 #endif
 
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+int request_firmware_direct(const struct firmware **fw, const char *name,
+			    struct device *device);
+#else
+#define request_firmware_direct	request_firmware
+#endif
+
 #endif
-- 
1.8.4.2

[PATCH v3 2/4] microcode: Use request_firmware_direct()

[Takashi Iwai]

Use the new helper, request_firmware_direct(), for avoiding the
lengthy timeout of non-existing firmware loads.  Especially the Intel
microcode driver suffers from this problem because each CPU triggers
the f/w loading, thus it ends up taking (literally) hours with many
cores.

Tested-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
 arch/x86/kernel/microcode_amd.c   | 2 +-
 arch/x86/kernel/microcode_intel.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index af99f71aeb7f..539a01a91210 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -430,7 +430,7 @@ static enum ucode_state request_microcode_amd(int cpu, struct device *device,
 	if (c->x86 >= 0x15)
 		snprintf(fw_name, sizeof(fw_name), "amd-ucode/microcode_amd_fam%.2xh.bin", c->x86);
 
-	if (request_firmware(&fw, (const char *)fw_name, device)) {
+	if (request_firmware_direct(&fw, (const char *)fw_name, device)) {
 		pr_err("failed to load file %s\n", fw_name);
 		goto out;
 	}
diff --git a/arch/x86/kernel/microcode_intel.c b/arch/x86/kernel/microcode_intel.c
index 5fb2cebf556b..a276fa75d9b5 100644
--- a/arch/x86/kernel/microcode_intel.c
+++ b/arch/x86/kernel/microcode_intel.c
@@ -278,7 +278,7 @@ static enum ucode_state request_microcode_fw(int cpu, struct device *device,
 	sprintf(name, "intel-ucode/%02x-%02x-%02x",
 		c->x86, c->x86_model, c->x86_mask);
 
-	if (request_firmware(&firmware, name, device)) {
+	if (request_firmware_direct(&firmware, name, device)) {
 		pr_debug("data file %s load failed\n", name);
 		return UCODE_NFOUND;
 	}
-- 
1.8.4.2

[PATCH v3 3/4] firmware: Use bit flags instead of boolean combos

[Takashi Iwai]

More than two boolean arguments to a function are rather confusing and
error-prone for callers.  Let's make the behavior bit flags instead of
triple combos.

A nice suggestion by Borislav Petkov.

Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
 drivers/base/firmware_class.c | 51 ++++++++++++++++++++++++-------------------
 1 file changed, 29 insertions(+), 22 deletions(-)

diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index 1af03648daf8..65797742c6b6 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -96,6 +96,11 @@ static inline long firmware_loading_timeout(void)
 	return loading_timeout > 0 ? loading_timeout * HZ : MAX_SCHEDULE_TIMEOUT;
 }
 
+/* firmware behavior options */
+#define FW_OPT_UEVENT	(1U << 0)
+#define FW_OPT_NOWAIT	(1U << 1)
+#define FW_OPT_FALLBACK	(1U << 2)
+
 struct firmware_cache {
 	/* firmware_buf instance will be added into the below list */
 	spinlock_t lock;
@@ -820,7 +825,7 @@ static void firmware_class_timeout_work(struct work_struct *work)
 
 static struct firmware_priv *
 fw_create_instance(struct firmware *firmware, const char *fw_name,
-		   struct device *device, bool uevent, bool nowait)
+		   struct device *device, unsigned int opt_flags)
 {
 	struct firmware_priv *fw_priv;
 	struct device *f_dev;
@@ -832,7 +837,7 @@ fw_create_instance(struct firmware *firmware, const char *fw_name,
 		goto exit;
 	}
 
-	fw_priv->nowait = nowait;
+	fw_priv->nowait = !!(opt_flags & FW_OPT_NOWAIT);
 	fw_priv->fw = firmware;
 	INIT_DELAYED_WORK(&fw_priv->timeout_work,
 		firmware_class_timeout_work);
@@ -848,8 +853,8 @@ exit:
 }
 
 /* load a firmware via user helper */
-static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
-				  long timeout)
+static int _request_firmware_load(struct firmware_priv *fw_priv,
+				  unsigned int opt_flags, long timeout)
 {
 	int retval = 0;
 	struct device *f_dev = &fw_priv->dev;
@@ -885,7 +890,7 @@ static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
 		goto err_del_bin_attr;
 	}
 
-	if (uevent) {
+	if (opt_flags & FW_OPT_UEVENT) {
 		buf->need_uevent = true;
 		dev_set_uevent_suppress(f_dev, false);
 		dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
@@ -911,16 +916,16 @@ err_put_dev:
 
 static int fw_load_from_user_helper(struct firmware *firmware,
 				    const char *name, struct device *device,
-				    bool uevent, bool nowait, long timeout)
+				    unsigned int opt_flags, long timeout)
 {
 	struct firmware_priv *fw_priv;
 
-	fw_priv = fw_create_instance(firmware, name, device, uevent, nowait);
+	fw_priv = fw_create_instance(firmware, name, device, opt_flags);
 	if (IS_ERR(fw_priv))
 		return PTR_ERR(fw_priv);
 
 	fw_priv->buf = firmware->priv;
-	return _request_firmware_load(fw_priv, uevent, timeout);
+	return _request_firmware_load(fw_priv, opt_flags, timeout);
 }
 
 #ifdef CONFIG_PM_SLEEP
@@ -942,7 +947,7 @@ static void kill_requests_without_uevent(void)
 #else /* CONFIG_FW_LOADER_USER_HELPER */
 static inline int
 fw_load_from_user_helper(struct firmware *firmware, const char *name,
-			 struct device *device, bool uevent, bool nowait,
+			 struct device *device, unsigned int opt_flags,
 			 long timeout)
 {
 	return -ENOENT;
@@ -1023,7 +1028,7 @@ _request_firmware_prepare(struct firmware **firmware_p, const char *name,
 }
 
 static int assign_firmware_buf(struct firmware *fw, struct device *device,
-				bool skip_cache)
+			       unsigned int opt_flags)
 {
 	struct firmware_buf *buf = fw->priv;
 
@@ -1040,7 +1045,8 @@ static int assign_firmware_buf(struct firmware *fw, struct device *device,
 	 * device may has been deleted already, but the problem
 	 * should be fixed in devres or driver core.
 	 */
-	if (device && !skip_cache)
+	/* don't cache firmware handled without uevent */
+	if (device && (opt_flags & FW_OPT_UEVENT))
 		fw_add_devm_name(device, buf->fw_id);
 
 	/*
@@ -1061,7 +1067,7 @@ static int assign_firmware_buf(struct firmware *fw, struct device *device,
 /* called from request_firmware() and request_firmware_work_func() */
 static int
 _request_firmware(const struct firmware **firmware_p, const char *name,
-		  struct device *device, bool uevent, bool nowait, bool fallback)
+		  struct device *device, unsigned int opt_flags)
 {
 	struct firmware *fw;
 	long timeout;
@@ -1076,7 +1082,7 @@ _request_firmware(const struct firmware **firmware_p, const char *name,
 
 	ret = 0;
 	timeout = firmware_loading_timeout();
-	if (nowait) {
+	if (opt_flags & FW_OPT_NOWAIT) {
 		timeout = usermodehelper_read_lock_wait(timeout);
 		if (!timeout) {
 			dev_dbg(device, "firmware: %s loading timed out\n",
@@ -1095,19 +1101,18 @@ _request_firmware(const struct firmware **firmware_p, const char *name,
 
 	ret = fw_get_filesystem_firmware(device, fw->priv);
 	if (ret) {
-		if (fallback) {
+		if (opt_flags & FW_OPT_FALLBACK) {
 			dev_warn(device,
 				 "Direct firmware load failed with error %d\n",
 				 ret);
 			dev_warn(device, "Falling back to user helper\n");
 			ret = fw_load_from_user_helper(fw, name, device,
-					       uevent, nowait, timeout);
+						       opt_flags, timeout);
 		}
 	}
 
-	/* don't cache firmware handled without uevent */
 	if (!ret)
-		ret = assign_firmware_buf(fw, device, !uevent);
+		ret = assign_firmware_buf(fw, device, opt_flags);
 
 	usermodehelper_read_unlock();
 
@@ -1149,7 +1154,8 @@ request_firmware(const struct firmware **firmware_p, const char *name,
 
 	/* Need to pin this module until return */
 	__module_get(THIS_MODULE);
-	ret = _request_firmware(firmware_p, name, device, true, false, true);
+	ret = _request_firmware(firmware_p, name, device,
+				FW_OPT_UEVENT | FW_OPT_FALLBACK);
 	module_put(THIS_MODULE);
 	return ret;
 }
@@ -1172,7 +1178,7 @@ int request_firmware_direct(const struct firmware **firmware_p,
 {
 	int ret;
 	__module_get(THIS_MODULE);
-	ret = _request_firmware(firmware_p, name, device, true, false, false);
+	ret = _request_firmware(firmware_p, name, device, FW_OPT_UEVENT);
 	module_put(THIS_MODULE);
 	return ret;
 }
@@ -1201,7 +1207,7 @@ struct firmware_work {
 	struct device *device;
 	void *context;
 	void (*cont)(const struct firmware *fw, void *context);
-	bool uevent;
+	unsigned int opt_flags;
 };
 
 static void request_firmware_work_func(struct work_struct *work)
@@ -1212,7 +1218,7 @@ static void request_firmware_work_func(struct work_struct *work)
 	fw_work = container_of(work, struct firmware_work, work);
 
 	_request_firmware(&fw, fw_work->name, fw_work->device,
-			  fw_work->uevent, true, true);
+			  fw_work->opt_flags);
 	fw_work->cont(fw, fw_work->context);
 	put_device(fw_work->device); /* taken in request_firmware_nowait() */
 
@@ -1260,7 +1266,8 @@ request_firmware_nowait(
 	fw_work->device = device;
 	fw_work->context = context;
 	fw_work->cont = cont;
-	fw_work->uevent = uevent;
+	fw_work->opt_flags = FW_OPT_NOWAIT | FW_OPT_FALLBACK |
+		(uevent ? FW_OPT_UEVENT : 0);
 
 	if (!try_module_get(module)) {
 		kfree(fw_work);
-- 
1.8.4.2

[PATCH v3 4/4] firmware: Suppress fallback warnings when CONFIG_FW_LOADER_USER_HELPER=n

[Takashi Iwai]

The commit [3e358ac2bb5b: firmware: Be a bit more verbose about direct
firmware loading failure] introduced a new warning message about
falling back to user helper, but this isn't true when
CONFIG_FW_LOADER_USER_HELPER isn't set.

In this patch, clear the FW_OPT_FALLBACK flag in the case without
userhelper, so that the corresponding code will be disabled.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
 drivers/base/firmware_class.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index 65797742c6b6..33b87bf664ab 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -99,7 +99,11 @@ static inline long firmware_loading_timeout(void)
 /* firmware behavior options */
 #define FW_OPT_UEVENT	(1U << 0)
 #define FW_OPT_NOWAIT	(1U << 1)
+#ifdef CONFIG_FW_LOADER_USER_HELPER
 #define FW_OPT_FALLBACK	(1U << 2)
+#else
+#define FW_OPT_FALLBACK	0
+#endif
 
 struct firmware_cache {
 	/* firmware_buf instance will be added into the below list */
-- 
1.8.4.2

Re: [PATCH v3 0/4] Add request_firmware_direct() for microcode loader

[Takashi Iwai]

At Tue, 12 Nov 2013 13:02:12 +0100,
Takashi Iwai wrote:
> 
> Hi,
> 
> this is a revised patch series to introduce request_firmware_direct()
> helper for avoiding the lengthy udev issue on microcode loader.
> The original problem was stated in Prarit's post:
>    https://lkml.org/lkml/2013/10/28/221
> 
> In short, microcode loader probes non-existing firmware files (which
> are cases with every new chip), and each probe takes 60 seconds,
> resulting in too long time until completed.
> 
> This solution is simply avoiding the udev fallback in
> request_firmware() explicitly for drivers like microcode.
> 
> Of course, this doesn't mean to throw away further optimizations like
> Prarit's patch.  It can be implemented in parallel with this.
> 
> 
>  [PATCH v3 1/4] firmware: Introduce request_firmware_direct()
>  [PATCH v3 2/4] microcode: Use request_firmware_direct()
>  [PATCH v3 3/4] firmware: Use bit flags instead of boolean combos
>  [PATCH v3 4/4] firmware: Suppress fallback warnings when CONFIG_FW_LOADER_USER_HELPER=n
> 
> v1->v2: Rebased on linux-next, add a fix for a bogus warning message
> v2->v3: Convert to bit flags, fix warning message differently
> 
> 
> Greg, could you take these patches through your driver tree, as
> most of fixes are about the firmware loader itself.

Greg, any chance to take a look at these patches?


thanks,

Takashi

Re: [PATCH v3 0/4] Add request_firmware_direct() for microcode loader

[Greg Kroah-Hartman]

On Fri, Nov 15, 2013 at 04:34:09PM +0100, Takashi Iwai wrote:
> At Tue, 12 Nov 2013 13:02:12 +0100,
> Takashi Iwai wrote:
> > 
> > Hi,
> > 
> > this is a revised patch series to introduce request_firmware_direct()
> > helper for avoiding the lengthy udev issue on microcode loader.
> > The original problem was stated in Prarit's post:
> >    https://lkml.org/lkml/2013/10/28/221
> > 
> > In short, microcode loader probes non-existing firmware files (which
> > are cases with every new chip), and each probe takes 60 seconds,
> > resulting in too long time until completed.
> > 
> > This solution is simply avoiding the udev fallback in
> > request_firmware() explicitly for drivers like microcode.
> > 
> > Of course, this doesn't mean to throw away further optimizations like
> > Prarit's patch.  It can be implemented in parallel with this.
> > 
> > 
> >  [PATCH v3 1/4] firmware: Introduce request_firmware_direct()
> >  [PATCH v3 2/4] microcode: Use request_firmware_direct()
> >  [PATCH v3 3/4] firmware: Use bit flags instead of boolean combos
> >  [PATCH v3 4/4] firmware: Suppress fallback warnings when CONFIG_FW_LOADER_USER_HELPER=n
> > 
> > v1->v2: Rebased on linux-next, add a fix for a bogus warning message
> > v2->v3: Convert to bit flags, fix warning message differently
> > 
> > 
> > Greg, could you take these patches through your driver tree, as
> > most of fixes are about the firmware loader itself.
> 
> Greg, any chance to take a look at these patches?

I'm traveling at the moment, in Korea this week.  I'll take a look at
them after 3.13-rc1 is out, as I can't do anything with patches until
then.  Don't worry, they aren't lost.

thanks,

greg k-h

Re: [PATCH v3 0/4] Add request_firmware_direct() for microcode loader

[Takashi Iwai]

At Sat, 16 Nov 2013 06:24:55 +0900,
Greg Kroah-Hartman wrote:
> 
> On Fri, Nov 15, 2013 at 04:34:09PM +0100, Takashi Iwai wrote:
> > At Tue, 12 Nov 2013 13:02:12 +0100,
> > Takashi Iwai wrote:
> > > 
> > > Hi,
> > > 
> > > this is a revised patch series to introduce request_firmware_direct()
> > > helper for avoiding the lengthy udev issue on microcode loader.
> > > The original problem was stated in Prarit's post:
> > >    https://lkml.org/lkml/2013/10/28/221
> > > 
> > > In short, microcode loader probes non-existing firmware files (which
> > > are cases with every new chip), and each probe takes 60 seconds,
> > > resulting in too long time until completed.
> > > 
> > > This solution is simply avoiding the udev fallback in
> > > request_firmware() explicitly for drivers like microcode.
> > > 
> > > Of course, this doesn't mean to throw away further optimizations like
> > > Prarit's patch.  It can be implemented in parallel with this.
> > > 
> > > 
> > >  [PATCH v3 1/4] firmware: Introduce request_firmware_direct()
> > >  [PATCH v3 2/4] microcode: Use request_firmware_direct()
> > >  [PATCH v3 3/4] firmware: Use bit flags instead of boolean combos
> > >  [PATCH v3 4/4] firmware: Suppress fallback warnings when CONFIG_FW_LOADER_USER_HELPER=n
> > > 
> > > v1->v2: Rebased on linux-next, add a fix for a bogus warning message
> > > v2->v3: Convert to bit flags, fix warning message differently
> > > 
> > > 
> > > Greg, could you take these patches through your driver tree, as
> > > most of fixes are about the firmware loader itself.
> > 
> > Greg, any chance to take a look at these patches?
> 
> I'm traveling at the moment, in Korea this week.  I'll take a look at
> them after 3.13-rc1 is out, as I can't do anything with patches until
> then.

Ah, I vaguely remember that.

> Don't worry, they aren't lost.

OK, thanks!


Takashi

Re: [PATCH v3 0/4] Add request_firmware_direct() for microcode loader

[Takashi Iwai]

At Sat, 16 Nov 2013 06:24:55 +0900,
Greg Kroah-Hartman wrote:
> 
> On Fri, Nov 15, 2013 at 04:34:09PM +0100, Takashi Iwai wrote:
> > At Tue, 12 Nov 2013 13:02:12 +0100,
> > Takashi Iwai wrote:
> > > 
> > > Hi,
> > > 
> > > this is a revised patch series to introduce request_firmware_direct()
> > > helper for avoiding the lengthy udev issue on microcode loader.
> > > The original problem was stated in Prarit's post:
> > >    https://lkml.org/lkml/2013/10/28/221
> > > 
> > > In short, microcode loader probes non-existing firmware files (which
> > > are cases with every new chip), and each probe takes 60 seconds,
> > > resulting in too long time until completed.
> > > 
> > > This solution is simply avoiding the udev fallback in
> > > request_firmware() explicitly for drivers like microcode.
> > > 
> > > Of course, this doesn't mean to throw away further optimizations like
> > > Prarit's patch.  It can be implemented in parallel with this.
> > > 
> > > 
> > >  [PATCH v3 1/4] firmware: Introduce request_firmware_direct()
> > >  [PATCH v3 2/4] microcode: Use request_firmware_direct()
> > >  [PATCH v3 3/4] firmware: Use bit flags instead of boolean combos
> > >  [PATCH v3 4/4] firmware: Suppress fallback warnings when CONFIG_FW_LOADER_USER_HELPER=n
> > > 
> > > v1->v2: Rebased on linux-next, add a fix for a bogus warning message
> > > v2->v3: Convert to bit flags, fix warning message differently
> > > 
> > > 
> > > Greg, could you take these patches through your driver tree, as
> > > most of fixes are about the firmware loader itself.
> > 
> > Greg, any chance to take a look at these patches?
> 
> I'm traveling at the moment, in Korea this week.  I'll take a look at
> them after 3.13-rc1 is out, as I can't do anything with patches until
> then.  Don't worry, they aren't lost.

They seem lost in Korea in the end :)
Could you catch up if still OK?

One of the patches seems slightly conflicting with the latest Linus
tree.  I can send a rebased one if needed, or you can take it from
  git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-unstable.git test/fw-direct


thanks,

Takashi

Re: [PATCH v3 0/4] Add request_firmware_direct() for microcode loader

[Greg Kroah-Hartman]

On Mon, Dec 02, 2013 at 09:44:13AM +0100, Takashi Iwai wrote:
> At Sat, 16 Nov 2013 06:24:55 +0900,
> Greg Kroah-Hartman wrote:
> > 
> > On Fri, Nov 15, 2013 at 04:34:09PM +0100, Takashi Iwai wrote:
> > > At Tue, 12 Nov 2013 13:02:12 +0100,
> > > Takashi Iwai wrote:
> > > > 
> > > > Hi,
> > > > 
> > > > this is a revised patch series to introduce request_firmware_direct()
> > > > helper for avoiding the lengthy udev issue on microcode loader.
> > > > The original problem was stated in Prarit's post:
> > > >    https://lkml.org/lkml/2013/10/28/221
> > > > 
> > > > In short, microcode loader probes non-existing firmware files (which
> > > > are cases with every new chip), and each probe takes 60 seconds,
> > > > resulting in too long time until completed.
> > > > 
> > > > This solution is simply avoiding the udev fallback in
> > > > request_firmware() explicitly for drivers like microcode.
> > > > 
> > > > Of course, this doesn't mean to throw away further optimizations like
> > > > Prarit's patch.  It can be implemented in parallel with this.
> > > > 
> > > > 
> > > >  [PATCH v3 1/4] firmware: Introduce request_firmware_direct()
> > > >  [PATCH v3 2/4] microcode: Use request_firmware_direct()
> > > >  [PATCH v3 3/4] firmware: Use bit flags instead of boolean combos
> > > >  [PATCH v3 4/4] firmware: Suppress fallback warnings when CONFIG_FW_LOADER_USER_HELPER=n
> > > > 
> > > > v1->v2: Rebased on linux-next, add a fix for a bogus warning message
> > > > v2->v3: Convert to bit flags, fix warning message differently
> > > > 
> > > > 
> > > > Greg, could you take these patches through your driver tree, as
> > > > most of fixes are about the firmware loader itself.
> > > 
> > > Greg, any chance to take a look at these patches?
> > 
> > I'm traveling at the moment, in Korea this week.  I'll take a look at
> > them after 3.13-rc1 is out, as I can't do anything with patches until
> > then.  Don't worry, they aren't lost.
> 
> They seem lost in Korea in the end :)

No, not lost:
	$ mdfrm -c ~/mail/todo/
	2485 messages in /home/gregkh/mail/todo/

Just burried :(

> Could you catch up if still OK?

I'll get to them soon...

> One of the patches seems slightly conflicting with the latest Linus
> tree.  I can send a rebased one if needed, or you can take it from
>   git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-unstable.git test/fw-direct

Yes please, an update would be good to have, can you just send this in
email form?

thanks,

greg k-h

Re: [PATCH v3 0/4] Add request_firmware_direct() for microcode loader

[Takashi Iwai]

At Mon, 2 Dec 2013 06:32:45 -0800,
Greg Kroah-Hartman wrote:
> 
> On Mon, Dec 02, 2013 at 09:44:13AM +0100, Takashi Iwai wrote:
> > At Sat, 16 Nov 2013 06:24:55 +0900,
> > Greg Kroah-Hartman wrote:
> > > 
> > > On Fri, Nov 15, 2013 at 04:34:09PM +0100, Takashi Iwai wrote:
> > > > At Tue, 12 Nov 2013 13:02:12 +0100,
> > > > Takashi Iwai wrote:
> > > > > 
> > > > > Hi,
> > > > > 
> > > > > this is a revised patch series to introduce request_firmware_direct()
> > > > > helper for avoiding the lengthy udev issue on microcode loader.
> > > > > The original problem was stated in Prarit's post:
> > > > >    https://lkml.org/lkml/2013/10/28/221
> > > > > 
> > > > > In short, microcode loader probes non-existing firmware files (which
> > > > > are cases with every new chip), and each probe takes 60 seconds,
> > > > > resulting in too long time until completed.
> > > > > 
> > > > > This solution is simply avoiding the udev fallback in
> > > > > request_firmware() explicitly for drivers like microcode.
> > > > > 
> > > > > Of course, this doesn't mean to throw away further optimizations like
> > > > > Prarit's patch.  It can be implemented in parallel with this.
> > > > > 
> > > > > 
> > > > >  [PATCH v3 1/4] firmware: Introduce request_firmware_direct()
> > > > >  [PATCH v3 2/4] microcode: Use request_firmware_direct()
> > > > >  [PATCH v3 3/4] firmware: Use bit flags instead of boolean combos
> > > > >  [PATCH v3 4/4] firmware: Suppress fallback warnings when CONFIG_FW_LOADER_USER_HELPER=n
> > > > > 
> > > > > v1->v2: Rebased on linux-next, add a fix for a bogus warning message
> > > > > v2->v3: Convert to bit flags, fix warning message differently
> > > > > 
> > > > > 
> > > > > Greg, could you take these patches through your driver tree, as
> > > > > most of fixes are about the firmware loader itself.
> > > > 
> > > > Greg, any chance to take a look at these patches?
> > > 
> > > I'm traveling at the moment, in Korea this week.  I'll take a look at
> > > them after 3.13-rc1 is out, as I can't do anything with patches until
> > > then.  Don't worry, they aren't lost.
> > 
> > They seem lost in Korea in the end :)
> 
> No, not lost:
> 	$ mdfrm -c ~/mail/todo/
> 	2485 messages in /home/gregkh/mail/todo/
> 
> Just burried :(

Wow, impressive numbers...

> > Could you catch up if still OK?
> 
> I'll get to them soon...
> 
> > One of the patches seems slightly conflicting with the latest Linus
> > tree.  I can send a rebased one if needed, or you can take it from
> >   git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-unstable.git test/fw-direct
> 
> Yes please, an update would be good to have, can you just send this in
> email form?

Alright, will do soon.


thanks,

Takashi