| Message ID | 1510891992-31659-1-git-send-email-mario.limonciello@dell.com (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Delegated to: | Darren Hart |
| Headers | show |
On Thu, Nov 16, 2017 at 10:13:12PM -0600, Mario Limonciello wrote: > The Dell SMBIOS WMI interface will fail for some more complex calls unless > a WMI hotfix has been included. Most platforms have this fix available in > a maintenance BIOS release. In the case the driver is loaded on a > platform without this fix, disable the userspace interface. > > A hotfix indicator is present in the dell-wmi-descriptor that represents > whether or not more complex calls will work properly. > > "Simple" calls such as those used by dell-laptop and dell-wmi will continue > to work properly so dell-smbios-wmi should not be blocked from binding and > being used as the dell-smbios dispatcher. > > Suggested-by: Girish Prakash <girish.prakash@dell.com> > Signed-off-by: Mario Limonciello <mario.limonciello@dell.com> Queued up, thanks Mario.
> -----Original Message----- > From: Darren Hart [mailto:dvhart@infradead.org] > Sent: Friday, November 17, 2017 2:39 PM > To: Limonciello, Mario <Mario_Limonciello@Dell.com> > Cc: Andy Shevchenko <andy.shevchenko@gmail.com>; LKML <linux- > kernel@vger.kernel.org>; platform-driver-x86@vger.kernel.org > Subject: Re: [PATCH v2] platform/x86: dell-smbios-wmi: Disable userspace > interface if missing hotfix > > On Thu, Nov 16, 2017 at 10:13:12PM -0600, Mario Limonciello wrote: > > The Dell SMBIOS WMI interface will fail for some more complex calls unless > > a WMI hotfix has been included. Most platforms have this fix available in > > a maintenance BIOS release. In the case the driver is loaded on a > > platform without this fix, disable the userspace interface. > > > > A hotfix indicator is present in the dell-wmi-descriptor that represents > > whether or not more complex calls will work properly. > > > > "Simple" calls such as those used by dell-laptop and dell-wmi will continue > > to work properly so dell-smbios-wmi should not be blocked from binding and > > being used as the dell-smbios dispatcher. > > > > Suggested-by: Girish Prakash <girish.prakash@dell.com> > > Signed-off-by: Mario Limonciello <mario.limonciello@dell.com> > > Queued up, thanks Mario. Darren, even though this came after the merge windows opened considering this restricts the SMBIOS interface from some platform/firmware combinations it shouldn't be offered, do you think this can be included with a future 4.15 RCx PR so it can land with the rest of the series rather than targeted for 4.16? I'd hate to get stuck in a situation that an interface deemed "broken" gets offered to people it shouldn't.
On Mon, Nov 20, 2017 at 04:03:53PM +0000, Mario.Limonciello@dell.com wrote: > > -----Original Message----- > > From: Darren Hart [mailto:dvhart@infradead.org] > > Sent: Friday, November 17, 2017 2:39 PM > > To: Limonciello, Mario <Mario_Limonciello@Dell.com> > > Cc: Andy Shevchenko <andy.shevchenko@gmail.com>; LKML <linux- > > kernel@vger.kernel.org>; platform-driver-x86@vger.kernel.org > > Subject: Re: [PATCH v2] platform/x86: dell-smbios-wmi: Disable userspace > > interface if missing hotfix > > > > On Thu, Nov 16, 2017 at 10:13:12PM -0600, Mario Limonciello wrote: > > > The Dell SMBIOS WMI interface will fail for some more complex calls unless > > > a WMI hotfix has been included. Most platforms have this fix available in > > > a maintenance BIOS release. In the case the driver is loaded on a > > > platform without this fix, disable the userspace interface. > > > > > > A hotfix indicator is present in the dell-wmi-descriptor that represents > > > whether or not more complex calls will work properly. > > > > > > "Simple" calls such as those used by dell-laptop and dell-wmi will continue > > > to work properly so dell-smbios-wmi should not be blocked from binding and > > > being used as the dell-smbios dispatcher. > > > > > > Suggested-by: Girish Prakash <girish.prakash@dell.com> > > > Signed-off-by: Mario Limonciello <mario.limonciello@dell.com> > > > > Queued up, thanks Mario. > > Darren, even though this came after the merge windows opened considering this > restricts the SMBIOS interface from some platform/firmware combinations it > shouldn't be offered, do you think this can be included with a future 4.15 > RCx PR so it can land with the rest of the series rather than targeted for 4.16? This will make 4.15. > > I'd hate to get stuck in a situation that an interface deemed "broken" gets offered > to people it shouldn't. > Agreed.
diff --git a/drivers/platform/x86/dell-smbios-wmi.c b/drivers/platform/x86/dell-smbios-wmi.c index 8ad11ef..044a104 100644 --- a/drivers/platform/x86/dell-smbios-wmi.c +++ b/drivers/platform/x86/dell-smbios-wmi.c @@ -147,7 +147,10 @@ static long dell_smbios_wmi_filter(struct wmi_device *wdev, unsigned int cmd, static int dell_smbios_wmi_probe(struct wmi_device *wdev) { + struct wmi_driver *wdriver = + container_of(wdev->dev.driver, struct wmi_driver, driver); struct wmi_smbios_priv *priv; + u32 hotfix; int count; int ret; @@ -167,6 +170,16 @@ static int dell_smbios_wmi_probe(struct wmi_device *wdev) if (!dell_wmi_get_size(&priv->req_buf_size)) return -EPROBE_DEFER; + /* some SMBIOS calls fail unless BIOS contains hotfix */ + if (!dell_wmi_get_hotfix(&hotfix)) + return -EPROBE_DEFER; + if (!hotfix) { + dev_warn(&wdev->dev, + "WMI SMBIOS userspace interface not supported(%u), try upgrading to a newer BIOS\n", + hotfix); + wdriver->filter_callback = NULL; + } + /* add in the length object we will use internally with ioctl */ priv->req_buf_size += sizeof(u64); ret = set_required_buffer_size(wdev, priv->req_buf_size); diff --git a/drivers/platform/x86/dell-wmi-descriptor.c b/drivers/platform/x86/dell-wmi-descriptor.c index e7f4c3a..5083ce0 100644 --- a/drivers/platform/x86/dell-wmi-descriptor.c +++ b/drivers/platform/x86/dell-wmi-descriptor.c @@ -25,6 +25,7 @@ struct descriptor_priv { struct list_head list; u32 interface_version; u32 size; + u32 hotfix; }; static int descriptor_valid = -EPROBE_DEFER; static LIST_HEAD(wmi_list); @@ -72,6 +73,24 @@ bool dell_wmi_get_size(u32 *size) } EXPORT_SYMBOL_GPL(dell_wmi_get_size); +bool dell_wmi_get_hotfix(u32 *hotfix) +{ + struct descriptor_priv *priv; + bool ret = false; + + mutex_lock(&list_mutex); + priv = list_first_entry_or_null(&wmi_list, + struct descriptor_priv, + list); + if (priv) { + *hotfix = priv->hotfix; + ret = true; + } + mutex_unlock(&list_mutex); + return ret; +} +EXPORT_SYMBOL_GPL(dell_wmi_get_hotfix); + /* * Descriptor buffer is 128 byte long and contains: * @@ -80,6 +99,7 @@ EXPORT_SYMBOL_GPL(dell_wmi_get_size); * Object Signature 4 4 " WMI" * WMI Interface Version 8 4 <version> * WMI buffer length 12 4 <length> + * WMI hotfix number 16 4 <hotfix> */ static int dell_wmi_descriptor_probe(struct wmi_device *wdev) { @@ -139,15 +159,17 @@ static int dell_wmi_descriptor_probe(struct wmi_device *wdev) priv->interface_version = buffer[2]; priv->size = buffer[3]; + priv->hotfix = buffer[4]; ret = 0; dev_set_drvdata(&wdev->dev, priv); mutex_lock(&list_mutex); list_add_tail(&priv->list, &wmi_list); mutex_unlock(&list_mutex); - dev_dbg(&wdev->dev, "Detected Dell WMI interface version %lu and buffer size %lu\n", + dev_dbg(&wdev->dev, "Detected Dell WMI interface version %lu, buffer size %lu, hotfix %lu\n", (unsigned long) priv->interface_version, - (unsigned long) priv->size); + (unsigned long) priv->size, + (unsigned long) priv->hotfix); out: kfree(obj); diff --git a/drivers/platform/x86/dell-wmi-descriptor.h b/drivers/platform/x86/dell-wmi-descriptor.h index 776cddd..217b833 100644 --- a/drivers/platform/x86/dell-wmi-descriptor.h +++ b/drivers/platform/x86/dell-wmi-descriptor.h @@ -24,5 +24,6 @@ int dell_wmi_get_descriptor_valid(void); bool dell_wmi_get_interface_version(u32 *version); bool dell_wmi_get_size(u32 *size); +bool dell_wmi_get_hotfix(u32 *hotfix); #endif
The Dell SMBIOS WMI interface will fail for some more complex calls unless a WMI hotfix has been included. Most platforms have this fix available in a maintenance BIOS release. In the case the driver is loaded on a platform without this fix, disable the userspace interface. A hotfix indicator is present in the dell-wmi-descriptor that represents whether or not more complex calls will work properly. "Simple" calls such as those used by dell-laptop and dell-wmi will continue to work properly so dell-smbios-wmi should not be blocked from binding and being used as the dell-smbios dispatcher. Suggested-by: Girish Prakash <girish.prakash@dell.com> Signed-off-by: Mario Limonciello <mario.limonciello@dell.com> --- drivers/platform/x86/dell-smbios-wmi.c | 13 +++++++++++++ drivers/platform/x86/dell-wmi-descriptor.c | 26 ++++++++++++++++++++++++-- drivers/platform/x86/dell-wmi-descriptor.h | 1 + 3 files changed, 38 insertions(+), 2 deletions(-)