| Message ID | 9b705747a138c96c26faee5218f7b47403195b28.1442305897.git.viresh.kumar@linaro.org |
|---|---|
| State | New |
| Headers | show |
On Tuesday, September 15, 2015 02:04:58 PM Viresh Kumar wrote: > global_lock is defined as an unsigned long and accessing only its lower > 32 bits from sysfs is incorrect, as we need to consider other 32 bits > for big endian 64 bit systems. > > Fix that by making global_lock an u32 instead. > > Cc: <stable@vger.kernel.org> # v4.1+ > Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> > > --- > Its marked just for # v4.1+, because arm64 has the first 64 big-endian > platform with ACPI. And ACPI support for that is mainlined recently > only (Arnd Bergmann). OK So are you aware of any ARM platform implementing the ACPI EC? I am not. Moreover, I'm not aware of any plans in that area. > Another thing worth noticing is that, global_lock is getting an unsigned > long long value assigned to it in ec_parse_device() and this is what > Arnd had to say about that: > > "I think that's fine, it does this because the _GLP variable in ACPI is > defined as an u64. And that's what happens on 32-bit architectures > anyway." > > This patch should go via GregKH, as the second patch has dependency on > it. > > V2->V3: > - Moved this out in a separate patch, so that it can be backported. Lv, can you have a look at this, please? > --- > drivers/acpi/ec_sys.c | 2 +- > drivers/acpi/internal.h | 2 +- > 2 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/acpi/ec_sys.c b/drivers/acpi/ec_sys.c > index b4c216bab22b..bea8e425a8de 100644 > --- a/drivers/acpi/ec_sys.c > +++ b/drivers/acpi/ec_sys.c > @@ -128,7 +128,7 @@ static int acpi_ec_add_debugfs(struct acpi_ec *ec, unsigned int ec_device_count) > if (!debugfs_create_x32("gpe", 0444, dev_dir, (u32 *)&first_ec->gpe)) > goto error; > if (!debugfs_create_bool("use_global_lock", 0444, dev_dir, > - (u32 *)&first_ec->global_lock)) > + &first_ec->global_lock)) > goto error; > > if (write_support) > diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h > index 9e426210c2a8..9db196de003c 100644 > --- a/drivers/acpi/internal.h > +++ b/drivers/acpi/internal.h > @@ -138,7 +138,7 @@ struct acpi_ec { > unsigned long gpe; > unsigned long command_addr; > unsigned long data_addr; > - unsigned long global_lock; > + u32 global_lock; > unsigned long flags; > unsigned long reference_count; > struct mutex mutex; > Thanks, Rafael -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 16-09-15, 04:06, Rafael J. Wysocki wrote: > In any case, please just split the EC-related changes off from your second > patch and send them separately. That !! change isn't required anymore, will be dropping it completely.
On Wednesday, September 16, 2015 03:57:05 AM Rafael J. Wysocki wrote: > On Tuesday, September 15, 2015 02:04:58 PM Viresh Kumar wrote: > > global_lock is defined as an unsigned long and accessing only its lower > > 32 bits from sysfs is incorrect, as we need to consider other 32 bits > > for big endian 64 bit systems. > > > > Fix that by making global_lock an u32 instead. > > > > Cc: <stable@vger.kernel.org> # v4.1+ > > Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> > > > > --- > > Its marked just for # v4.1+, because arm64 has the first 64 big-endian > > platform with ACPI. And ACPI support for that is mainlined recently > > only (Arnd Bergmann). > > OK > > So are you aware of any ARM platform implementing the ACPI EC? > > I am not. Moreover, I'm not aware of any plans in that area. In any case, please just split the EC-related changes off from your second patch and send them separately. Thanks, Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi, > From: Rafael J. Wysocki [mailto:rjw@rjwysocki.net] > Sent: Wednesday, September 16, 2015 9:57 AM > > On Tuesday, September 15, 2015 02:04:58 PM Viresh Kumar wrote: > > global_lock is defined as an unsigned long and accessing only its lower > > 32 bits from sysfs is incorrect, as we need to consider other 32 bits > > for big endian 64 bit systems. > > > > Fix that by making global_lock an u32 instead. > > > > Cc: <stable@vger.kernel.org> # v4.1+ > > Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> > > > > --- > > Its marked just for # v4.1+, because arm64 has the first 64 big-endian > > platform with ACPI. And ACPI support for that is mainlined recently > > only (Arnd Bergmann). > > OK > > So are you aware of any ARM platform implementing the ACPI EC? > > I am not. Moreover, I'm not aware of any plans in that area. > > > Another thing worth noticing is that, global_lock is getting an unsigned > > long long value assigned to it in ec_parse_device() and this is what > > Arnd had to say about that: > > > > "I think that's fine, it does this because the _GLP variable in ACPI is > > defined as an u64. And that's what happens on 32-bit architectures > > anyway." > > > > This patch should go via GregKH, as the second patch has dependency on > > it. > > > > V2->V3: > > - Moved this out in a separate patch, so that it can be backported. > > Lv, can you have a look at this, please? > > > --- > > drivers/acpi/ec_sys.c | 2 +- > > drivers/acpi/internal.h | 2 +- > > 2 files changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/acpi/ec_sys.c b/drivers/acpi/ec_sys.c > > index b4c216bab22b..bea8e425a8de 100644 > > --- a/drivers/acpi/ec_sys.c > > +++ b/drivers/acpi/ec_sys.c > > @@ -128,7 +128,7 @@ static int acpi_ec_add_debugfs(struct acpi_ec *ec, unsigned int ec_device_count) > > if (!debugfs_create_x32("gpe", 0444, dev_dir, (u32 *)&first_ec->gpe)) > > goto error; > > if (!debugfs_create_bool("use_global_lock", 0444, dev_dir, > > - (u32 *)&first_ec->global_lock)) > > + &first_ec->global_lock)) > > goto error; > > > > if (write_support) > > diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h > > index 9e426210c2a8..9db196de003c 100644 > > --- a/drivers/acpi/internal.h > > +++ b/drivers/acpi/internal.h > > @@ -138,7 +138,7 @@ struct acpi_ec { > > unsigned long gpe; > > unsigned long command_addr; > > unsigned long data_addr; > > - unsigned long global_lock; > > + u32 global_lock; > > unsigned long flags; > > unsigned long reference_count; > > struct mutex mutex; > > > If we really want to change, we may change everything here. gpe/command_addr/data_addr/global_lock. And IMO, if we really want to change global_lock, we should make it bool here. Thanks and best regards -Lv > Thanks, > Rafael N§˛ćěr¸yúčŘb˛XŹśÇ§vŘ^)Ţş{.nÇ+ˇĽ{ąęçzX§śĄÜ¨}Š˛Ć zÚ&j:+v¨žŤęçzZ+Ę+zfŁ˘ˇh§~Űi˙űŕzš ŽwĽ˘¸?¨čÚ&˘)ߢfů^jÇŤy§m á@AŤaśÚ˙ 0śěhŽĺi
On 15/09/15 09:34, Viresh Kumar wrote: > global_lock is defined as an unsigned long and accessing only its lower > 32 bits from sysfs is incorrect, as we need to consider other 32 bits > for big endian 64 bit systems. > > Fix that by making global_lock an u32 instead. > > Cc: <stable@vger.kernel.org> # v4.1+ > Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> > > --- > Its marked just for # v4.1+, because arm64 has the first 64 big-endian > platform with ACPI. And ACPI support for that is mainlined recently > only (Arnd Bergmann). > Just to clarify, we don't support big-endian with ACPI on ARM64. We mandate use of EFI for ACPI on ARM64 and EFI spec mandates only little endian. Regards, Sudeep -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 23/09/15 10:39, Arnd Bergmann wrote: > On Wednesday 23 September 2015 10:15:42 Sudeep Holla wrote: >> On 15/09/15 09:34, Viresh Kumar wrote: >>> global_lock is defined as an unsigned long and accessing only its lower >>> 32 bits from sysfs is incorrect, as we need to consider other 32 bits >>> for big endian 64 bit systems. >>> >>> Fix that by making global_lock an u32 instead. >>> >>> Cc: <stable@vger.kernel.org> # v4.1+ >>> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> >>> >>> --- >>> Its marked just for # v4.1+, because arm64 has the first 64 big-endian >>> platform with ACPI. And ACPI support for that is mainlined recently >>> only (Arnd Bergmann). >>> >> >> Just to clarify, we don't support big-endian with ACPI on ARM64. >> We mandate use of EFI for ACPI on ARM64 and EFI spec mandates only >> little endian. >> > > EFI doesn't care what endianess the kernel has, as long as the > data structures are interpreted in the same way that the firmware > defines them, and I thought that at least UEFI on ARM64 with big-endian > is working in principle (if not, that is a bug that should be fixed). > > If ACPI is broken with big-endian kernels, we should probably add a > Kconfig statement to forbid it, like this: > The diff looks sensible thing to have to avoid enabling ACPI with BE though I am not sure if this can be regarded as broken as it could be case of just not supported(my guess as I am not completely aware of the history). Also I am not against the $subject patch as such, just added clarification so that it shouldn't be assumed that BE + ACPI works on ARM64. Regards, Sudeep > diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig > index 5d1015c26ff4..06cacc13e3d2 100644 > --- a/drivers/acpi/Kconfig > +++ b/drivers/acpi/Kconfig > @@ -6,6 +6,7 @@ menuconfig ACPI > bool "ACPI (Advanced Configuration and Power Interface) Support" > depends on !IA64_HP_SIM > depends on IA64 || X86 || (ARM64 && EXPERT) > + depends on !ARM64 || !CPU_BIG_ENDIAN || BROKEN > depends on PCI > select PNP > default y > > > Arnd > -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wednesday 23 September 2015 10:57:44 Sudeep Holla wrote: > > Also I am not against the $subject patch as such, just added > clarification so that it shouldn't be assumed that BE + ACPI works on > ARM64. > Ok, at least we can safely assume that we do not need to backport that patch to stable then. Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
On 23-09-15, 07:52, Zheng, Lv wrote:
> And IMO, if we really want to change global_lock, we should make it bool here.
Yeah, so the second patch in this series is doing just that. Just kept
this patch separate to make more sense. Will resend both and keep you
in cc.
On 25-09-15, 02:17, Rafael J. Wysocki wrote: > Actually, what about adding a local u32 variable, say val, here and doing > > > if (!debugfs_create_x32("gpe", 0444, dev_dir, (u32 *)&first_ec->gpe)) > > goto error; > > if (!debugfs_create_bool("use_global_lock", 0444, dev_dir, > > - (u32 *)&first_ec->global_lock)) > > + &first_ec->global_lock)) > > if (!debugfs_create_bool("use_global_lock", 0444, dev_dir, &val)) > > > goto error; > > first_ec->global_lock = val; > > And then you can turn val into bool just fine without changing the structure > definition. sure. Looks good.
On Tuesday, September 15, 2015 02:04:58 PM Viresh Kumar wrote: > global_lock is defined as an unsigned long and accessing only its lower > 32 bits from sysfs is incorrect, as we need to consider other 32 bits > for big endian 64 bit systems. > > Fix that by making global_lock an u32 instead. > > Cc: <stable@vger.kernel.org> # v4.1+ > Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> > > --- > Its marked just for # v4.1+, because arm64 has the first 64 big-endian > platform with ACPI. And ACPI support for that is mainlined recently > only (Arnd Bergmann). > > Another thing worth noticing is that, global_lock is getting an unsigned > long long value assigned to it in ec_parse_device() and this is what > Arnd had to say about that: > > "I think that's fine, it does this because the _GLP variable in ACPI is > defined as an u64. And that's what happens on 32-bit architectures > anyway." > > This patch should go via GregKH, as the second patch has dependency on > it. > > V2->V3: > - Moved this out in a separate patch, so that it can be backported. > --- > drivers/acpi/ec_sys.c | 2 +- > drivers/acpi/internal.h | 2 +- > 2 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/acpi/ec_sys.c b/drivers/acpi/ec_sys.c > index b4c216bab22b..bea8e425a8de 100644 > --- a/drivers/acpi/ec_sys.c > +++ b/drivers/acpi/ec_sys.c > @@ -128,7 +128,7 @@ static int acpi_ec_add_debugfs(struct acpi_ec *ec, unsigned int ec_device_count) Actually, what about adding a local u32 variable, say val, here and doing > if (!debugfs_create_x32("gpe", 0444, dev_dir, (u32 *)&first_ec->gpe)) > goto error; > if (!debugfs_create_bool("use_global_lock", 0444, dev_dir, > - (u32 *)&first_ec->global_lock)) > + &first_ec->global_lock)) if (!debugfs_create_bool("use_global_lock", 0444, dev_dir, &val)) > goto error; first_ec->global_lock = val; And then you can turn val into bool just fine without changing the structure definition. > > if (write_support) > diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h > index 9e426210c2a8..9db196de003c 100644 > --- a/drivers/acpi/internal.h > +++ b/drivers/acpi/internal.h > @@ -138,7 +138,7 @@ struct acpi_ec { > unsigned long gpe; > unsigned long command_addr; > unsigned long data_addr; > - unsigned long global_lock; > + u32 global_lock; > unsigned long flags; > unsigned long reference_count; > struct mutex mutex; > Thanks, Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/acpi/ec_sys.c b/drivers/acpi/ec_sys.c index b4c216bab22b..bea8e425a8de 100644 --- a/drivers/acpi/ec_sys.c +++ b/drivers/acpi/ec_sys.c @@ -128,7 +128,7 @@ static int acpi_ec_add_debugfs(struct acpi_ec *ec, unsigned int ec_device_count) if (!debugfs_create_x32("gpe", 0444, dev_dir, (u32 *)&first_ec->gpe)) goto error; if (!debugfs_create_bool("use_global_lock", 0444, dev_dir, - (u32 *)&first_ec->global_lock)) + &first_ec->global_lock)) goto error; if (write_support) diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h index 9e426210c2a8..9db196de003c 100644 --- a/drivers/acpi/internal.h +++ b/drivers/acpi/internal.h @@ -138,7 +138,7 @@ struct acpi_ec { unsigned long gpe; unsigned long command_addr; unsigned long data_addr; - unsigned long global_lock; + u32 global_lock; unsigned long flags; unsigned long reference_count; struct mutex mutex;
global_lock is defined as an unsigned long and accessing only its lower 32 bits from sysfs is incorrect, as we need to consider other 32 bits for big endian 64 bit systems. Fix that by making global_lock an u32 instead. Cc: <stable@vger.kernel.org> # v4.1+ Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> --- Its marked just for # v4.1+, because arm64 has the first 64 big-endian platform with ACPI. And ACPI support for that is mainlined recently only (Arnd Bergmann). Another thing worth noticing is that, global_lock is getting an unsigned long long value assigned to it in ec_parse_device() and this is what Arnd had to say about that: "I think that's fine, it does this because the _GLP variable in ACPI is defined as an u64. And that's what happens on 32-bit architectures anyway." This patch should go via GregKH, as the second patch has dependency on it. V2->V3: - Moved this out in a separate patch, so that it can be backported. --- drivers/acpi/ec_sys.c | 2 +- drivers/acpi/internal.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)