| Message ID | 20210504174019.2134652-1-linux@roeck-us.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iio: bme680_i2c: Make bme680_acpi_match depend on CONFIG_ACPI | expand |
On Tue, May 4, 2021 at 8:40 PM Guenter Roeck <linux@roeck-us.net> wrote: > > With CONFIG_ACPI=n and -Werror, 0-day reports: > > drivers/iio/chemical/bme680_i2c.c:46:36: error: > 'bme680_acpi_match' defined but not used > Given the other patch, question of course is if this ACPI ID > is real. A Google search suggests that this might not be the case. > Should we remove it as well ? STK8312 has the same problem. For this one definitely removal. Looking into the code it suggests a cargo cult taken that time by a few contributors to invent fake ACPI IDs while submitting new drivers. Feel free to add my tag or if you wish me I'll add it explicitly.
On Tue, May 4, 2021 at 8:44 PM Andy Shevchenko <andy.shevchenko@gmail.com> wrote: > > On Tue, May 4, 2021 at 8:40 PM Guenter Roeck <linux@roeck-us.net> wrote: > > > > With CONFIG_ACPI=n and -Werror, 0-day reports: > > > > drivers/iio/chemical/bme680_i2c.c:46:36: error: > > 'bme680_acpi_match' defined but not used > > > Given the other patch, question of course is if this ACPI ID > > is real. A Google search suggests that this might not be the case. > > Should we remove it as well ? STK8312 has the same problem. > > For this one definitely removal. Looking into the code it suggests a > cargo cult taken that time by a few contributors to invent fake ACPI > IDs while submitting new drivers. > Feel free to add my tag or if you wish me I'll add it explicitly. Had just looked at STK, the same guy as for AOS2315. So, also to remove.
On 5/4/21 10:44 AM, Andy Shevchenko wrote: > On Tue, May 4, 2021 at 8:40 PM Guenter Roeck <linux@roeck-us.net> wrote: >> >> With CONFIG_ACPI=n and -Werror, 0-day reports: >> >> drivers/iio/chemical/bme680_i2c.c:46:36: error: >> 'bme680_acpi_match' defined but not used > >> Given the other patch, question of course is if this ACPI ID >> is real. A Google search suggests that this might not be the case. >> Should we remove it as well ? STK8312 has the same problem. > > For this one definitely removal. Looking into the code it suggests a > cargo cult taken that time by a few contributors to invent fake ACPI > IDs while submitting new drivers. > Feel free to add my tag or if you wish me I'll add it explicitly. > I'll resend and let you add the tag, and send a similar patch for STK8312. I'll wait until tomorrow, though - I sent a number of patches today already, and I want to avoid yet another "account suspended" notice from gmail. Thanks, Guenter
On Tue, 4 May 2021 11:00:52 -0700 Guenter Roeck <linux@roeck-us.net> wrote: > On 5/4/21 10:44 AM, Andy Shevchenko wrote: > > On Tue, May 4, 2021 at 8:40 PM Guenter Roeck <linux@roeck-us.net> wrote: > >> > >> With CONFIG_ACPI=n and -Werror, 0-day reports: > >> > >> drivers/iio/chemical/bme680_i2c.c:46:36: error: > >> 'bme680_acpi_match' defined but not used > > > >> Given the other patch, question of course is if this ACPI ID > >> is real. A Google search suggests that this might not be the case. > >> Should we remove it as well ? STK8312 has the same problem. > > > > For this one definitely removal. Looking into the code it suggests a > > cargo cult taken that time by a few contributors to invent fake ACPI > > IDs while submitting new drivers. > > Feel free to add my tag or if you wish me I'll add it explicitly. > > > > I'll resend and let you add the tag, and send a similar patch > for STK8312. I'll wait until tomorrow, though - I sent a number of > patches today already, and I want to avoid yet another "account > suspended" notice from gmail. If you find some valid ACPI entries that are hitting this problem, I'd prefer we just got rid of the ACPI_PTR() usecases rather than added IFDEF magic. The space wasted by having these is trivial and I'd rather not introduce ifdef around any of these tables. Dropping the ones we are fairly sure are spurious is even better! Thanks, Jonathan > > Thanks, > Guenter
On Wed, 5 May 2021 09:32:35 +0100 Jonathan Cameron <Jonathan.Cameron@Huawei.com> wrote: > On Tue, 4 May 2021 11:00:52 -0700 > Guenter Roeck <linux@roeck-us.net> wrote: > > > On 5/4/21 10:44 AM, Andy Shevchenko wrote: > > > On Tue, May 4, 2021 at 8:40 PM Guenter Roeck <linux@roeck-us.net> wrote: > > >> > > >> With CONFIG_ACPI=n and -Werror, 0-day reports: > > >> > > >> drivers/iio/chemical/bme680_i2c.c:46:36: error: > > >> 'bme680_acpi_match' defined but not used > > > > > >> Given the other patch, question of course is if this ACPI ID > > >> is real. A Google search suggests that this might not be the case. > > >> Should we remove it as well ? STK8312 has the same problem. > > > > > > For this one definitely removal. Looking into the code it suggests a > > > cargo cult taken that time by a few contributors to invent fake ACPI > > > IDs while submitting new drivers. > > > Feel free to add my tag or if you wish me I'll add it explicitly. > > > > > > > I'll resend and let you add the tag, and send a similar patch > > for STK8312. I'll wait until tomorrow, though - I sent a number of > > patches today already, and I want to avoid yet another "account > > suspended" notice from gmail. > > If you find some valid ACPI entries that are hitting this problem, > I'd prefer we just got rid of the ACPI_PTR() usecases rather than > added IFDEF magic. > > The space wasted by having these is trivial and I'd rather not > introduce ifdef around any of these tables. > > Dropping the ones we are fairly sure are spurious is even better! If I get bored I'll just do a scrub of all the instances of this that you haven't already cleaned up. It's worth noting that we do know some highly suspicious looking entries are out there in the wild. Thanks, Jonathan > > Thanks, > > Jonathan > > > > > Thanks, > > Guenter >
On Wed, May 5, 2021 at 11:34 AM Jonathan Cameron <Jonathan.Cameron@huawei.com> wrote: > On Tue, 4 May 2021 11:00:52 -0700 > Guenter Roeck <linux@roeck-us.net> wrote: > > On 5/4/21 10:44 AM, Andy Shevchenko wrote: > > > On Tue, May 4, 2021 at 8:40 PM Guenter Roeck <linux@roeck-us.net> wrote: > > I'll resend and let you add the tag, and send a similar patch > > for STK8312. I'll wait until tomorrow, though - I sent a number of > > patches today already, and I want to avoid yet another "account > > suspended" notice from gmail. > > If you find some valid ACPI entries that are hitting this problem, > I'd prefer we just got rid of the ACPI_PTR() usecases rather than > added IFDEF magic. Agree, > The space wasted by having these is trivial and I'd rather not > introduce ifdef around any of these tables. > Dropping the ones we are fairly sure are spurious is even better! For the record, I have checked all three Guenter pointed out and to me all of them sounds like fake (two from the same author). So, I can deduce that if we have same author for a few looking very suspicious ACPI IDs, they are quite likely fake and must be removed sooner than later.
On Wed, May 05, 2021 at 09:34:38AM +0100, Jonathan Cameron wrote: > On Wed, 5 May 2021 09:32:35 +0100 > Jonathan Cameron <Jonathan.Cameron@Huawei.com> wrote: > > > On Tue, 4 May 2021 11:00:52 -0700 > > Guenter Roeck <linux@roeck-us.net> wrote: > > > > > On 5/4/21 10:44 AM, Andy Shevchenko wrote: > > > > On Tue, May 4, 2021 at 8:40 PM Guenter Roeck <linux@roeck-us.net> wrote: > > > >> > > > >> With CONFIG_ACPI=n and -Werror, 0-day reports: > > > >> > > > >> drivers/iio/chemical/bme680_i2c.c:46:36: error: > > > >> 'bme680_acpi_match' defined but not used > > > > > > > >> Given the other patch, question of course is if this ACPI ID > > > >> is real. A Google search suggests that this might not be the case. > > > >> Should we remove it as well ? STK8312 has the same problem. > > > > > > > > For this one definitely removal. Looking into the code it suggests a > > > > cargo cult taken that time by a few contributors to invent fake ACPI > > > > IDs while submitting new drivers. > > > > Feel free to add my tag or if you wish me I'll add it explicitly. > > > > > > > > > > I'll resend and let you add the tag, and send a similar patch > > > for STK8312. I'll wait until tomorrow, though - I sent a number of > > > patches today already, and I want to avoid yet another "account > > > suspended" notice from gmail. > > > > If you find some valid ACPI entries that are hitting this problem, > > I'd prefer we just got rid of the ACPI_PTR() usecases rather than > > added IFDEF magic. > > > > The space wasted by having these is trivial and I'd rather not > > introduce ifdef around any of these tables. > > > > Dropping the ones we are fairly sure are spurious is even better! > > If I get bored I'll just do a scrub of all the instances of this that > you haven't already cleaned up. It's worth noting that we do > know some highly suspicious looking entries are out there in the wild. > The ones reported by 0-day are AOS2315, BME0680, and STK8312. You just accepted a patch for -next which claims that all users of STK8312 would be ACPI, yet Andy says that STK8312 isn't a valid ACPI ID. Not really sure from the above if I should send patches to remove acpi support from those drivers or if you want to handle that yourself. Other drivers such as FXOS8700 should also generate a warning with CONFIG_ACPI=n but for some reason don't. I have not tried to track down the reason. Anyway, for an "outsider" it seems all but impossible to determine if an ACPI ID is real or made up. How does one know ? Note that I didn't actually get any of your e-mails (nor, I notice, several other e-mails I was copied on). I picked this one up from the linux-kernel mailing list. My apologies if I don't reply to any of your e-mails; that would be the reason. Guenter
On Wed, May 5, 2021 at 11:36 AM Jonathan Cameron <Jonathan.Cameron@huawei.com> wrote: > On Wed, 5 May 2021 09:32:35 +0100 > Jonathan Cameron <Jonathan.Cameron@Huawei.com> wrote: > > On Tue, 4 May 2021 11:00:52 -0700 > > Guenter Roeck <linux@roeck-us.net> wrote: +Cc: Paul (I hope you are related to coreboot somehow and can communicate this further), Pavel and Jacek (LED subsystem suffered with this as well), Hans, Rafael and linux-acpi@ > > Dropping the ones we are fairly sure are spurious is even better! > > If I get bored I'll just do a scrub of all the instances of this that > you haven't already cleaned up. It's worth noting that we do > know some highly suspicious looking entries are out there in the wild. I have counted ~60 users of acpi_device_id in IIO. Brief looking at the IDs themselves rings an alarm about half of them. So, here we may have a chicken and egg problem, i.e. somebody has been using (or used) fake IDs from Linux kernel in the real products. What I can consider as a course of action is the following: 1. Clean up (by removing as quickly as possible) the IDs that have no proof to be real from the Linux kernel sources (perhaps marked as stable material) 2. Notify ASWG / UEFI forum about all IDs that abuse ACPI specification and are in Linux kernel, so at least we can keep some kind of "reserved/do not use" list on the official level (Rafael?) 3. Do not accept any IDs without an evidence provided that they are being in use in the real products (this should be done on Linux maintainer level in all subsystems that accept drivers
Hi, On 5/5/21 3:22 PM, Andy Shevchenko wrote: > On Wed, May 5, 2021 at 11:36 AM Jonathan Cameron > <Jonathan.Cameron@huawei.com> wrote: >> On Wed, 5 May 2021 09:32:35 +0100 >> Jonathan Cameron <Jonathan.Cameron@Huawei.com> wrote: >>> On Tue, 4 May 2021 11:00:52 -0700 >>> Guenter Roeck <linux@roeck-us.net> wrote: > > +Cc: Paul (I hope you are related to coreboot somehow and can > communicate this further), Pavel and Jacek (LED subsystem suffered > with this as well), Hans, Rafael and linux-acpi@ > >>> Dropping the ones we are fairly sure are spurious is even better! >> >> If I get bored I'll just do a scrub of all the instances of this that >> you haven't already cleaned up. It's worth noting that we do >> know some highly suspicious looking entries are out there in the wild. > > I have counted ~60 users of acpi_device_id in IIO. Brief looking at > the IDs themselves rings an alarm about half of them. > > So, here we may have a chicken and egg problem, i.e. somebody has been > using (or used) fake IDs from Linux kernel in the real products. What > I can consider as a course of action is the following: > 1. Clean up (by removing as quickly as possible) the IDs that have no > proof to be real from the Linux kernel sources (perhaps marked as > stable material) > 2. Notify ASWG / UEFI forum about all IDs that abuse ACPI > specification and are in Linux kernel, so at least we can keep some > kind of "reserved/do not use" list on the official level (Rafael?) > 3. Do not accept any IDs without an evidence provided that they are > being in use in the real products (this should be done on Linux > maintainer level in all subsystems that accept drivers So my 2 cents on this are that we need to be very careful with removing "bogus" ACPI-ids. A couple of examples from a quick check under drivers/iio/accel: drivers/iio/accel/bmc150-accel-i2c.c: static const struct i2c_device_id bmc150_accel_id[] = { {"bmc150_accel", bmc150}, {"bmi055_accel", bmi055}, {"bma255", bma255}, {"bma250e", bma250e}, {"bma222", bma222}, {"bma222e", bma222e}, {"bma280", bma280}, {} }; static const struct acpi_device_id bmc150_accel_acpi_match[] = { {"BSBA0150", bmc150}, {"BMC150A", bmc150}, {"BMI055A", bmi055}, {"BMA0255", bma255}, {"BMA250E", bma250e}, {"BMA222", bma222}, {"BMA222E", bma222e}, {"BMA0280", bma280}, {"BOSC0200"}, { }, }; With the exception of the "BSBA0150" and "BOSC0200" ids, these look like they were invented. But at least the "BMA250E" one is actually being used! The other BMA###? ones are probably fake, but given that the "BMA250E" one is actually real ... drivers/iio/accel/bmc150-accel-spi.c This uses the same set of ACPI ids as bmc150-accel-i2c.c minus the "BOSC0200" one. I'm not aware if these being used in spi mode on any x86 devices, but again I'm not 100% sure ... drivers/iio/accel/da280.c static const struct acpi_device_id da280_acpi_match[] = { {"MIRAACC", da280}, {}, }; MODULE_DEVICE_TABLE(acpi, da280_acpi_match); This looks like a fake-id, but it was actually added in a separate commit adding ACPI support because the chip is used with this id on a Linx 820 Windows tablet. So figuring out of any ids are real or not is really tricky and removing them if they are real will lead to regressions. So summarizing IMHO we need to be careful and not just start removing a whole bunch of these... Regards, Hans
On Wed, May 5, 2021 at 4:39 PM Hans de Goede <hdegoede@redhat.com> wrote: > On 5/5/21 3:22 PM, Andy Shevchenko wrote: > > On Wed, May 5, 2021 at 11:36 AM Jonathan Cameron > > <Jonathan.Cameron@huawei.com> wrote: > >> On Wed, 5 May 2021 09:32:35 +0100 > >> Jonathan Cameron <Jonathan.Cameron@Huawei.com> wrote: > >>> On Tue, 4 May 2021 11:00:52 -0700 > >>> Guenter Roeck <linux@roeck-us.net> wrote: > > > > +Cc: Paul (I hope you are related to coreboot somehow and can > > communicate this further), Pavel and Jacek (LED subsystem suffered > > with this as well), Hans, Rafael and linux-acpi@ > > > >>> Dropping the ones we are fairly sure are spurious is even better! > >> > >> If I get bored I'll just do a scrub of all the instances of this that > >> you haven't already cleaned up. It's worth noting that we do > >> know some highly suspicious looking entries are out there in the wild. > > > > I have counted ~60 users of acpi_device_id in IIO. Brief looking at > > the IDs themselves rings an alarm about half of them. > > > > So, here we may have a chicken and egg problem, i.e. somebody has been > > using (or used) fake IDs from Linux kernel in the real products. What > > I can consider as a course of action is the following: > > 1. Clean up (by removing as quickly as possible) the IDs that have no > > proof to be real from the Linux kernel sources (perhaps marked as > > stable material) > > 2. Notify ASWG / UEFI forum about all IDs that abuse ACPI > > specification and are in Linux kernel, so at least we can keep some > > kind of "reserved/do not use" list on the official level (Rafael?) > > 3. Do not accept any IDs without an evidence provided that they are > > being in use in the real products (this should be done on Linux > > maintainer level in all subsystems that accept drivers > > So my 2 cents on this are that we need to be very careful with > removing "bogus" ACPI-ids. > > A couple of examples from a quick check under drivers/iio/accel: > > drivers/iio/accel/bmc150-accel-i2c.c: > > static const struct i2c_device_id bmc150_accel_id[] = { > {"bmc150_accel", bmc150}, > {"bmi055_accel", bmi055}, > {"bma255", bma255}, > {"bma250e", bma250e}, > {"bma222", bma222}, > {"bma222e", bma222e}, > {"bma280", bma280}, > {} > }; > > static const struct acpi_device_id bmc150_accel_acpi_match[] = { > {"BSBA0150", bmc150}, > {"BMC150A", bmc150}, > {"BMI055A", bmi055}, > {"BMA0255", bma255}, > {"BMA250E", bma250e}, > {"BMA222", bma222}, > {"BMA222E", bma222e}, > {"BMA0280", bma280}, > {"BOSC0200"}, > { }, > }; > > With the exception of the "BSBA0150" and "BOSC0200" > ids, these look like they were invented. But at least the > "BMA250E" one is actually being used! The other BMA###? > ones are probably fake, but given that the "BMA250E" > one is actually real ... > > drivers/iio/accel/bmc150-accel-spi.c > > This uses the same set of ACPI ids as bmc150-accel-i2c.c > minus the "BOSC0200" one. I'm not aware if these > being used in spi mode on any x86 devices, but again > I'm not 100% sure ... > > drivers/iio/accel/da280.c > > static const struct acpi_device_id da280_acpi_match[] = { > {"MIRAACC", da280}, > {}, > }; > MODULE_DEVICE_TABLE(acpi, da280_acpi_match); > > This looks like a fake-id, but it was actually added > in a separate commit adding ACPI support because the > chip is used with this id on a Linx 820 Windows tablet. > > So figuring out of any ids are real or not is really tricky > and removing them if they are real will lead to regressions. > > So summarizing IMHO we need to be careful and not just > start removing a whole bunch of these... That's all true. However, I have a few hints on how to distinguish them (fake ones): 1. The ID has been added from day 1 with I2C or SPI ID table with just capitalized name 2. If there are a few drivers by the same author and at least one of the contributions has confirmed fake ID 3. The ID is single in the list and mimics the part number (capitalized form) 4. Google/DuckDuckGo/etc searches give no meaningful results Either combination of the above can be a good hint to at least be sceptical that it's being used. So, Hans, as you already noticed, drivers with a long list of IDs or when ID added separately can be considered less fakish, but we really want evidence of the hardware that has it. Some big companies sometimes produce fake IDs themselves (and sometimes for the components they are not even producing) without following the process (as described on uefi.org) which is a pity part of the story.
Hi, On 5/5/21 3:53 PM, Andy Shevchenko wrote: > On Wed, May 5, 2021 at 4:39 PM Hans de Goede <hdegoede@redhat.com> wrote: >> On 5/5/21 3:22 PM, Andy Shevchenko wrote: >>> On Wed, May 5, 2021 at 11:36 AM Jonathan Cameron >>> <Jonathan.Cameron@huawei.com> wrote: >>>> On Wed, 5 May 2021 09:32:35 +0100 >>>> Jonathan Cameron <Jonathan.Cameron@Huawei.com> wrote: >>>>> On Tue, 4 May 2021 11:00:52 -0700 >>>>> Guenter Roeck <linux@roeck-us.net> wrote: >>> >>> +Cc: Paul (I hope you are related to coreboot somehow and can >>> communicate this further), Pavel and Jacek (LED subsystem suffered >>> with this as well), Hans, Rafael and linux-acpi@ >>> >>>>> Dropping the ones we are fairly sure are spurious is even better! >>>> >>>> If I get bored I'll just do a scrub of all the instances of this that >>>> you haven't already cleaned up. It's worth noting that we do >>>> know some highly suspicious looking entries are out there in the wild. >>> >>> I have counted ~60 users of acpi_device_id in IIO. Brief looking at >>> the IDs themselves rings an alarm about half of them. >>> >>> So, here we may have a chicken and egg problem, i.e. somebody has been >>> using (or used) fake IDs from Linux kernel in the real products. What >>> I can consider as a course of action is the following: >>> 1. Clean up (by removing as quickly as possible) the IDs that have no >>> proof to be real from the Linux kernel sources (perhaps marked as >>> stable material) >>> 2. Notify ASWG / UEFI forum about all IDs that abuse ACPI >>> specification and are in Linux kernel, so at least we can keep some >>> kind of "reserved/do not use" list on the official level (Rafael?) >>> 3. Do not accept any IDs without an evidence provided that they are >>> being in use in the real products (this should be done on Linux >>> maintainer level in all subsystems that accept drivers >> >> So my 2 cents on this are that we need to be very careful with >> removing "bogus" ACPI-ids. >> >> A couple of examples from a quick check under drivers/iio/accel: >> >> drivers/iio/accel/bmc150-accel-i2c.c: >> >> static const struct i2c_device_id bmc150_accel_id[] = { >> {"bmc150_accel", bmc150}, >> {"bmi055_accel", bmi055}, >> {"bma255", bma255}, >> {"bma250e", bma250e}, >> {"bma222", bma222}, >> {"bma222e", bma222e}, >> {"bma280", bma280}, >> {} >> }; >> >> static const struct acpi_device_id bmc150_accel_acpi_match[] = { >> {"BSBA0150", bmc150}, >> {"BMC150A", bmc150}, >> {"BMI055A", bmi055}, >> {"BMA0255", bma255}, >> {"BMA250E", bma250e}, >> {"BMA222", bma222}, >> {"BMA222E", bma222e}, >> {"BMA0280", bma280}, >> {"BOSC0200"}, >> { }, >> }; >> >> With the exception of the "BSBA0150" and "BOSC0200" >> ids, these look like they were invented. But at least the >> "BMA250E" one is actually being used! The other BMA###? >> ones are probably fake, but given that the "BMA250E" >> one is actually real ... >> >> drivers/iio/accel/bmc150-accel-spi.c >> >> This uses the same set of ACPI ids as bmc150-accel-i2c.c >> minus the "BOSC0200" one. I'm not aware if these >> being used in spi mode on any x86 devices, but again >> I'm not 100% sure ... >> >> drivers/iio/accel/da280.c >> >> static const struct acpi_device_id da280_acpi_match[] = { >> {"MIRAACC", da280}, >> {}, >> }; >> MODULE_DEVICE_TABLE(acpi, da280_acpi_match); >> >> This looks like a fake-id, but it was actually added >> in a separate commit adding ACPI support because the >> chip is used with this id on a Linx 820 Windows tablet. >> >> So figuring out of any ids are real or not is really tricky >> and removing them if they are real will lead to regressions. >> >> So summarizing IMHO we need to be careful and not just >> start removing a whole bunch of these... > > That's all true. However, I have a few hints on how to distinguish > them (fake ones): > 1. The ID has been added from day 1 with I2C or SPI ID table with just > capitalized name > 2. If there are a few drivers by the same author and at least one of > the contributions has confirmed fake ID > 3. The ID is single in the list and mimics the part number (capitalized form) > 4. Google/DuckDuckGo/etc searches give no meaningful results > > Either combination of the above can be a good hint to at least be > sceptical that it's being used May I suggest for accelerometers to also grep for the id in 60-sensors.hwdb from systemd ? E.g. the BMA250E id can be found there. > So, Hans, as you already noticed, drivers with a long list of IDs or > when ID added separately can be considered less fakish, but we really > want evidence of the hardware that has it. If you want to move ahead with pruning some of these please Cc me on the patches, then I'll check them against my collection of Bay and Cherry Trail DSDTs, which are devices where these sensors are often found. Regards, Hans
On Wed, May 5, 2021 at 5:11 PM Hans de Goede <hdegoede@redhat.com> wrote: > On 5/5/21 3:53 PM, Andy Shevchenko wrote: > > On Wed, May 5, 2021 at 4:39 PM Hans de Goede <hdegoede@redhat.com> wrote: > >> On 5/5/21 3:22 PM, Andy Shevchenko wrote: > >>> On Wed, May 5, 2021 at 11:36 AM Jonathan Cameron > >>> <Jonathan.Cameron@huawei.com> wrote: > >>>> On Wed, 5 May 2021 09:32:35 +0100 > >>>> Jonathan Cameron <Jonathan.Cameron@Huawei.com> wrote: > >>>>> On Tue, 4 May 2021 11:00:52 -0700 > >>>>> Guenter Roeck <linux@roeck-us.net> wrote: > >>> > >>> +Cc: Paul (I hope you are related to coreboot somehow and can > >>> communicate this further), Pavel and Jacek (LED subsystem suffered > >>> with this as well), Hans, Rafael and linux-acpi@ > >>> > >>>>> Dropping the ones we are fairly sure are spurious is even better! > >>>> > >>>> If I get bored I'll just do a scrub of all the instances of this that > >>>> you haven't already cleaned up. It's worth noting that we do > >>>> know some highly suspicious looking entries are out there in the wild. > >>> > >>> I have counted ~60 users of acpi_device_id in IIO. Brief looking at > >>> the IDs themselves rings an alarm about half of them. > >>> > >>> So, here we may have a chicken and egg problem, i.e. somebody has been > >>> using (or used) fake IDs from Linux kernel in the real products. What > >>> I can consider as a course of action is the following: > >>> 1. Clean up (by removing as quickly as possible) the IDs that have no > >>> proof to be real from the Linux kernel sources (perhaps marked as > >>> stable material) > >>> 2. Notify ASWG / UEFI forum about all IDs that abuse ACPI > >>> specification and are in Linux kernel, so at least we can keep some > >>> kind of "reserved/do not use" list on the official level (Rafael?) > >>> 3. Do not accept any IDs without an evidence provided that they are > >>> being in use in the real products (this should be done on Linux > >>> maintainer level in all subsystems that accept drivers > >> > >> So my 2 cents on this are that we need to be very careful with > >> removing "bogus" ACPI-ids. > >> > >> A couple of examples from a quick check under drivers/iio/accel: > >> > >> drivers/iio/accel/bmc150-accel-i2c.c: > >> > >> static const struct i2c_device_id bmc150_accel_id[] = { > >> {"bmc150_accel", bmc150}, > >> {"bmi055_accel", bmi055}, > >> {"bma255", bma255}, > >> {"bma250e", bma250e}, > >> {"bma222", bma222}, > >> {"bma222e", bma222e}, > >> {"bma280", bma280}, > >> {} > >> }; > >> > >> static const struct acpi_device_id bmc150_accel_acpi_match[] = { > >> {"BSBA0150", bmc150}, > >> {"BMC150A", bmc150}, > >> {"BMI055A", bmi055}, > >> {"BMA0255", bma255}, > >> {"BMA250E", bma250e}, > >> {"BMA222", bma222}, > >> {"BMA222E", bma222e}, > >> {"BMA0280", bma280}, > >> {"BOSC0200"}, > >> { }, > >> }; > >> > >> With the exception of the "BSBA0150" and "BOSC0200" > >> ids, these look like they were invented. But at least the > >> "BMA250E" one is actually being used! The other BMA###? > >> ones are probably fake, but given that the "BMA250E" > >> one is actually real ... > >> > >> drivers/iio/accel/bmc150-accel-spi.c > >> > >> This uses the same set of ACPI ids as bmc150-accel-i2c.c > >> minus the "BOSC0200" one. I'm not aware if these > >> being used in spi mode on any x86 devices, but again > >> I'm not 100% sure ... > >> > >> drivers/iio/accel/da280.c > >> > >> static const struct acpi_device_id da280_acpi_match[] = { > >> {"MIRAACC", da280}, > >> {}, > >> }; > >> MODULE_DEVICE_TABLE(acpi, da280_acpi_match); > >> > >> This looks like a fake-id, but it was actually added > >> in a separate commit adding ACPI support because the > >> chip is used with this id on a Linx 820 Windows tablet. > >> > >> So figuring out of any ids are real or not is really tricky > >> and removing them if they are real will lead to regressions. > >> > >> So summarizing IMHO we need to be careful and not just > >> start removing a whole bunch of these... > > > > That's all true. However, I have a few hints on how to distinguish > > them (fake ones): > > 1. The ID has been added from day 1 with I2C or SPI ID table with just > > capitalized name > > 2. If there are a few drivers by the same author and at least one of > > the contributions has confirmed fake ID > > 3. The ID is single in the list and mimics the part number (capitalized form) > > 4. Google/DuckDuckGo/etc searches give no meaningful results > > > > Either combination of the above can be a good hint to at least be > > sceptical that it's being used > May I suggest for accelerometers to also grep for the id in > 60-sensors.hwdb from systemd ? E.g. the BMA250E id can be found > there. Right, it's a very good suggestion! It will definitely tell us what may not be removed even if we don't see any evidence otherwise. > > So, Hans, as you already noticed, drivers with a long list of IDs or > > when ID added separately can be considered less fakish, but we really > > want evidence of the hardware that has it. > > If you want to move ahead with pruning some of these please Cc me > on the patches, then I'll check them against my collection of > Bay and Cherry Trail DSDTs, which are devices where these sensors > are often found. Currently the scope is of AOS2315 BME0680 STK8312
Hi, On 5/5/21 4:18 PM, Andy Shevchenko wrote: > On Wed, May 5, 2021 at 5:11 PM Hans de Goede <hdegoede@redhat.com> wrote: >> On 5/5/21 3:53 PM, Andy Shevchenko wrote: >>> On Wed, May 5, 2021 at 4:39 PM Hans de Goede <hdegoede@redhat.com> wrote: >>>> On 5/5/21 3:22 PM, Andy Shevchenko wrote: >>>>> On Wed, May 5, 2021 at 11:36 AM Jonathan Cameron >>>>> <Jonathan.Cameron@huawei.com> wrote: >>>>>> On Wed, 5 May 2021 09:32:35 +0100 >>>>>> Jonathan Cameron <Jonathan.Cameron@Huawei.com> wrote: >>>>>>> On Tue, 4 May 2021 11:00:52 -0700 >>>>>>> Guenter Roeck <linux@roeck-us.net> wrote: >>>>> >>>>> +Cc: Paul (I hope you are related to coreboot somehow and can >>>>> communicate this further), Pavel and Jacek (LED subsystem suffered >>>>> with this as well), Hans, Rafael and linux-acpi@ >>>>> >>>>>>> Dropping the ones we are fairly sure are spurious is even better! >>>>>> >>>>>> If I get bored I'll just do a scrub of all the instances of this that >>>>>> you haven't already cleaned up. It's worth noting that we do >>>>>> know some highly suspicious looking entries are out there in the wild. >>>>> >>>>> I have counted ~60 users of acpi_device_id in IIO. Brief looking at >>>>> the IDs themselves rings an alarm about half of them. >>>>> >>>>> So, here we may have a chicken and egg problem, i.e. somebody has been >>>>> using (or used) fake IDs from Linux kernel in the real products. What >>>>> I can consider as a course of action is the following: >>>>> 1. Clean up (by removing as quickly as possible) the IDs that have no >>>>> proof to be real from the Linux kernel sources (perhaps marked as >>>>> stable material) >>>>> 2. Notify ASWG / UEFI forum about all IDs that abuse ACPI >>>>> specification and are in Linux kernel, so at least we can keep some >>>>> kind of "reserved/do not use" list on the official level (Rafael?) >>>>> 3. Do not accept any IDs without an evidence provided that they are >>>>> being in use in the real products (this should be done on Linux >>>>> maintainer level in all subsystems that accept drivers >>>> >>>> So my 2 cents on this are that we need to be very careful with >>>> removing "bogus" ACPI-ids. >>>> >>>> A couple of examples from a quick check under drivers/iio/accel: >>>> >>>> drivers/iio/accel/bmc150-accel-i2c.c: >>>> >>>> static const struct i2c_device_id bmc150_accel_id[] = { >>>> {"bmc150_accel", bmc150}, >>>> {"bmi055_accel", bmi055}, >>>> {"bma255", bma255}, >>>> {"bma250e", bma250e}, >>>> {"bma222", bma222}, >>>> {"bma222e", bma222e}, >>>> {"bma280", bma280}, >>>> {} >>>> }; >>>> >>>> static const struct acpi_device_id bmc150_accel_acpi_match[] = { >>>> {"BSBA0150", bmc150}, >>>> {"BMC150A", bmc150}, >>>> {"BMI055A", bmi055}, >>>> {"BMA0255", bma255}, >>>> {"BMA250E", bma250e}, >>>> {"BMA222", bma222}, >>>> {"BMA222E", bma222e}, >>>> {"BMA0280", bma280}, >>>> {"BOSC0200"}, >>>> { }, >>>> }; >>>> >>>> With the exception of the "BSBA0150" and "BOSC0200" >>>> ids, these look like they were invented. But at least the >>>> "BMA250E" one is actually being used! The other BMA###? >>>> ones are probably fake, but given that the "BMA250E" >>>> one is actually real ... >>>> >>>> drivers/iio/accel/bmc150-accel-spi.c >>>> >>>> This uses the same set of ACPI ids as bmc150-accel-i2c.c >>>> minus the "BOSC0200" one. I'm not aware if these >>>> being used in spi mode on any x86 devices, but again >>>> I'm not 100% sure ... >>>> >>>> drivers/iio/accel/da280.c >>>> >>>> static const struct acpi_device_id da280_acpi_match[] = { >>>> {"MIRAACC", da280}, >>>> {}, >>>> }; >>>> MODULE_DEVICE_TABLE(acpi, da280_acpi_match); >>>> >>>> This looks like a fake-id, but it was actually added >>>> in a separate commit adding ACPI support because the >>>> chip is used with this id on a Linx 820 Windows tablet. >>>> >>>> So figuring out of any ids are real or not is really tricky >>>> and removing them if they are real will lead to regressions. >>>> >>>> So summarizing IMHO we need to be careful and not just >>>> start removing a whole bunch of these... >>> >>> That's all true. However, I have a few hints on how to distinguish >>> them (fake ones): >>> 1. The ID has been added from day 1 with I2C or SPI ID table with just >>> capitalized name >>> 2. If there are a few drivers by the same author and at least one of >>> the contributions has confirmed fake ID >>> 3. The ID is single in the list and mimics the part number (capitalized form) >>> 4. Google/DuckDuckGo/etc searches give no meaningful results >>> >>> Either combination of the above can be a good hint to at least be >>> sceptical that it's being used >> May I suggest for accelerometers to also grep for the id in >> 60-sensors.hwdb from systemd ? E.g. the BMA250E id can be found >> there. > > Right, it's a very good suggestion! It will definitely tell us what > may not be removed even if we don't see any evidence otherwise. > >>> So, Hans, as you already noticed, drivers with a long list of IDs or >>> when ID added separately can be considered less fakish, but we really >>> want evidence of the hardware that has it. >> >> If you want to move ahead with pruning some of these please Cc me >> on the patches, then I'll check them against my collection of >> Bay and Cherry Trail DSDTs, which are devices where these sensors >> are often found. > > Currently the scope is of > AOS2315 > BME0680 > STK8312 Ok I cannot find any reference to those in the DSDT-s which I have, nor in systemd's hwdb. Regards, Hans
On Wed, May 5, 2021 at 6:19 PM Hans de Goede <hdegoede@redhat.com> wrote: > On 5/5/21 4:18 PM, Andy Shevchenko wrote: > > On Wed, May 5, 2021 at 5:11 PM Hans de Goede <hdegoede@redhat.com> wrote: ... > > Currently the scope is of > > AOS2315 > > BME0680 > > STK8312 > > Ok I cannot find any reference to those in the DSDT-s which I have, > nor in systemd's hwdb. Thanks for checking. By the way. Do you have DSDTs in some kind of Git repository? Shouldn't we have (means to create if not exists) one publicly available? It would be nice to gather them under the hood for the purpose of looking into. I have some (small) set of those as well which might be useful.
Hi, On 5/5/21 6:26 PM, Andy Shevchenko wrote: > On Wed, May 5, 2021 at 6:19 PM Hans de Goede <hdegoede@redhat.com> wrote: >> On 5/5/21 4:18 PM, Andy Shevchenko wrote: >>> On Wed, May 5, 2021 at 5:11 PM Hans de Goede <hdegoede@redhat.com> wrote: > > ... > >>> Currently the scope is of >>> AOS2315 >>> BME0680 >>> STK8312 >> >> Ok I cannot find any reference to those in the DSDT-s which I have, >> nor in systemd's hwdb. > > Thanks for checking. > > By the way. Do you have DSDTs in some kind of Git repository? > Shouldn't we have (means to create if not exists) one publicly > available? It would be nice to gather them under the hood for the > purpose of looking into. I have some (small) set of those as well > which might be useful. Interesting idea, the issue is that arguably these are copyrightable and we don't have any permission to distribute them. Things like attaching them to bugs, having them emailed to me, etc. can be considered fair use of sorts I guess (IANAL), but putting them into a git repo would really be a bit of a grey area... Regards, Hans
Hi! On Wed 2021-05-05 16:22:07, Andy Shevchenko wrote: > On Wed, May 5, 2021 at 11:36 AM Jonathan Cameron > <Jonathan.Cameron@huawei.com> wrote: > > On Wed, 5 May 2021 09:32:35 +0100 > > Jonathan Cameron <Jonathan.Cameron@Huawei.com> wrote: > > > On Tue, 4 May 2021 11:00:52 -0700 > > > Guenter Roeck <linux@roeck-us.net> wrote: > > +Cc: Paul (I hope you are related to coreboot somehow and can > communicate this further), Pavel and Jacek (LED subsystem suffered > with this as well), Hans, Rafael and linux-acpi@ Thanks for Cc. I prefer @ucw.cz address for the LED work. > > > Dropping the ones we are fairly sure are spurious is even better! > > > > If I get bored I'll just do a scrub of all the instances of this that > > you haven't already cleaned up. It's worth noting that we do > > know some highly suspicious looking entries are out there in the wild. > > I have counted ~60 users of acpi_device_id in IIO. Brief looking at > the IDs themselves rings an alarm about half of them. As far as I can tell, this means asking "is this real ID or did you just invent it" at patch submission. Okay... Best regards, Pavel
On Fri, May 7, 2021 at 2:53 PM Pavel Machek <pavel@denx.de> wrote: > On Wed 2021-05-05 16:22:07, Andy Shevchenko wrote: > > On Wed, May 5, 2021 at 11:36 AM Jonathan Cameron > > <Jonathan.Cameron@huawei.com> wrote: > > > On Wed, 5 May 2021 09:32:35 +0100 > > > Jonathan Cameron <Jonathan.Cameron@Huawei.com> wrote: > > > > On Tue, 4 May 2021 11:00:52 -0700 > > > > Guenter Roeck <linux@roeck-us.net> wrote: > > > > +Cc: Paul (I hope you are related to coreboot somehow and can > > communicate this further), Pavel and Jacek (LED subsystem suffered > > with this as well), Hans, Rafael and linux-acpi@ > > Thanks for Cc. I prefer @ucw.cz address for the LED work. Noted! > > > > Dropping the ones we are fairly sure are spurious is even better! > > > > > > If I get bored I'll just do a scrub of all the instances of this that > > > you haven't already cleaned up. It's worth noting that we do > > > know some highly suspicious looking entries are out there in the wild. > > > > I have counted ~60 users of acpi_device_id in IIO. Brief looking at > > the IDs themselves rings an alarm about half of them. > > As far as I can tell, this means asking "is this real ID or did you > just invent it" at patch submission. Okay... I would put it in a way that "Please, provide an ASL excerpt / ACPI tables dump" or something alike. Because it may also show some additional information that would make sense to consider when adding an ID to the driver.
diff --git a/drivers/iio/chemical/bme680_i2c.c b/drivers/iio/chemical/bme680_i2c.c index 29c0dfa4702b..b5e75f145c19 100644 --- a/drivers/iio/chemical/bme680_i2c.c +++ b/drivers/iio/chemical/bme680_i2c.c @@ -42,11 +42,13 @@ static const struct i2c_device_id bme680_i2c_id[] = { }; MODULE_DEVICE_TABLE(i2c, bme680_i2c_id); +#ifdef CONFIG_ACPI static const struct acpi_device_id bme680_acpi_match[] = { {"BME0680", 0}, {}, }; MODULE_DEVICE_TABLE(acpi, bme680_acpi_match); +#endif static const struct of_device_id bme680_of_i2c_match[] = { { .compatible = "bosch,bme680", },
With CONFIG_ACPI=n and -Werror, 0-day reports: drivers/iio/chemical/bme680_i2c.c:46:36: error: 'bme680_acpi_match' defined but not used Reported-by: kernel test robot <lkp@intel.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> --- Given the other patch, question of course is if this ACPI ID is real. A Google search suggests that this might not be the case. Should we remove it as well ? STK8312 has the same problem. Jonathan, I think this needs your input before I send more patches. drivers/iio/chemical/bme680_i2c.c | 2 ++ 1 file changed, 2 insertions(+)