| Message ID | 20231227173757.1743001-1-pavan.kumar.linga@intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [iwl-net] idpf: avoid compiler padding in virtchnl2_ptype struct | expand |
Dear Pavan, Thank you for yoru patch. Am 27.12.23 um 18:37 schrieb Pavan Kumar Linga: > Config option in arm random config file Sorry, I do not understand this part of the sentence. What Kconfig option was selected exactly causing this behavior. > is causing the compiler > to add padding. Avoid it by using "__packed" structure attribute > for virtchnl2_ptype struct. Did the compiler emit a warning? If so, please paste it. > Fixes: 0d7502a9b4a7 ("virtchnl: add virtchnl version 2 ops") > Reported-by: kernel test robot <lkp@intel.com> > Closes: https://lore.kernel.org/oe-kbuild-all/202312220250.ufEm8doQ-lkp@intel.com > Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com> > Signed-off-by: Pavan Kumar Linga <pavan.kumar.linga@intel.com> > --- > drivers/net/ethernet/intel/idpf/virtchnl2.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/ethernet/intel/idpf/virtchnl2.h b/drivers/net/ethernet/intel/idpf/virtchnl2.h > index 8dc83788972..dd750e6dcd0 100644 > --- a/drivers/net/ethernet/intel/idpf/virtchnl2.h > +++ b/drivers/net/ethernet/intel/idpf/virtchnl2.h > @@ -978,7 +978,7 @@ struct virtchnl2_ptype { > u8 proto_id_count; > __le16 pad; > __le16 proto_id[]; > -}; > +} __packed; > VIRTCHNL2_CHECK_STRUCT_LEN(6, virtchnl2_ptype); > > /** Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de> Kind regards, Paul
On 12/27/2023 1:45 PM, Paul Menzel wrote: > Dear Pavan, > > > Thank you for yoru patch. > > Am 27.12.23 um 18:37 schrieb Pavan Kumar Linga: >> Config option in arm random config file > > Sorry, I do not understand this part of the sentence. What Kconfig > option was selected exactly causing this behavior. > Apologies as I couldn't find the config option that was causing this. As the driver compilation with arm rand config was failing, posted the fix first. Will debug further to find the config option that resulted in this failure. Thanks for the review. >> is causing the compiler >> to add padding. Avoid it by using "__packed" structure attribute >> for virtchnl2_ptype struct. > > Did the compiler emit a warning? If so, please paste it. > Here is the compiler error and also will update the commit message with the error: include/linux/build_bug.h:78:41: error: static assertion failed: "(6) == sizeof(struct virtchnl2_ptype)" 78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg) | ^~~~~~~~~~~~~~ include/linux/build_bug.h:77:34: note: in expansion of macro '__static_assert' 77 | #define static_assert(expr, ...) __static_assert(expr, ##__VA_ARGS__, #expr) | ^~~~~~~~~~~~~~~ drivers/net/ethernet/intel/idpf/virtchnl2.h:26:9: note: in expansion of macro 'static_assert' 26 | static_assert((n) == sizeof(struct X)) | ^~~~~~~~~~~~~ drivers/net/ethernet/intel/idpf/virtchnl2.h:982:1: note: in expansion of macro 'VIRTCHNL2_CHECK_STRUCT_LEN' 982 | VIRTCHNL2_CHECK_STRUCT_LEN(6, virtchnl2_ptype); | ^~~~~~~~~~~~~~~~~~~~~~~~~~ Regards, Pavan >> Fixes: 0d7502a9b4a7 ("virtchnl: add virtchnl version 2 ops") >> Reported-by: kernel test robot <lkp@intel.com> >> Closes: >> https://lore.kernel.org/oe-kbuild-all/202312220250.ufEm8doQ-lkp@intel.com >> Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com> >> Signed-off-by: Pavan Kumar Linga <pavan.kumar.linga@intel.com> >> --- >> drivers/net/ethernet/intel/idpf/virtchnl2.h | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/net/ethernet/intel/idpf/virtchnl2.h >> b/drivers/net/ethernet/intel/idpf/virtchnl2.h >> index 8dc83788972..dd750e6dcd0 100644 >> --- a/drivers/net/ethernet/intel/idpf/virtchnl2.h >> +++ b/drivers/net/ethernet/intel/idpf/virtchnl2.h >> @@ -978,7 +978,7 @@ struct virtchnl2_ptype { >> u8 proto_id_count; >> __le16 pad; >> __le16 proto_id[]; >> -}; >> +} __packed; >> VIRTCHNL2_CHECK_STRUCT_LEN(6, virtchnl2_ptype); >> /** > > Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de> > > > > Kind regards, > > Paul
On 12/28/2023 9:39 AM, Linga, Pavan Kumar wrote: > > > On 12/27/2023 1:45 PM, Paul Menzel wrote: >> Dear Pavan, >> >> >> Thank you for yoru patch. >> >> Am 27.12.23 um 18:37 schrieb Pavan Kumar Linga: >>> Config option in arm random config file >> >> Sorry, I do not understand this part of the sentence. What Kconfig >> option was selected exactly causing this behavior. >> > > Apologies as I couldn't find the config option that was causing this. As > the driver compilation with arm rand config was failing, posted the fix > first. Will debug further to find the config option that resulted in > this failure. Thanks for the review. > After further debug, found that the arm random config was using OABI (old ABI) which was inferred from the compiler option '-mabi=apcs-gnu'. kconfig option 'CONFIG_AEABI' is related to this and was disabled by default in the config file. Static assertion check passed when compiled the driver with 'CONFIG_AEABI' enabled. The check also passed on explicitly changing the compiler option to '-mabi=aapcs-linux'. I will update the commit message with this info. Regards, Pavan >>> is causing the compiler >>> to add padding. Avoid it by using "__packed" structure attribute >>> for virtchnl2_ptype struct. >> >> Did the compiler emit a warning? If so, please paste it. >> > > Here is the compiler error and also will update the commit message with > the error: > > include/linux/build_bug.h:78:41: error: static assertion failed: "(6) == > sizeof(struct virtchnl2_ptype)" > 78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, > msg) > | ^~~~~~~~~~~~~~ > include/linux/build_bug.h:77:34: note: in expansion of macro > '__static_assert' > 77 | #define static_assert(expr, ...) __static_assert(expr, > ##__VA_ARGS__, #expr) > | ^~~~~~~~~~~~~~~ > drivers/net/ethernet/intel/idpf/virtchnl2.h:26:9: note: in expansion > of macro 'static_assert' > 26 | static_assert((n) == sizeof(struct X)) > | ^~~~~~~~~~~~~ > drivers/net/ethernet/intel/idpf/virtchnl2.h:982:1: note: in > expansion of macro 'VIRTCHNL2_CHECK_STRUCT_LEN' > 982 | VIRTCHNL2_CHECK_STRUCT_LEN(6, virtchnl2_ptype); > | ^~~~~~~~~~~~~~~~~~~~~~~~~~ > > Regards, > Pavan > >>> Fixes: 0d7502a9b4a7 ("virtchnl: add virtchnl version 2 ops") >>> Reported-by: kernel test robot <lkp@intel.com> >>> Closes: >>> https://lore.kernel.org/oe-kbuild-all/202312220250.ufEm8doQ-lkp@intel.com >>> Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com> >>> Signed-off-by: Pavan Kumar Linga <pavan.kumar.linga@intel.com> >>> --- >>> drivers/net/ethernet/intel/idpf/virtchnl2.h | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/drivers/net/ethernet/intel/idpf/virtchnl2.h >>> b/drivers/net/ethernet/intel/idpf/virtchnl2.h >>> index 8dc83788972..dd750e6dcd0 100644 >>> --- a/drivers/net/ethernet/intel/idpf/virtchnl2.h >>> +++ b/drivers/net/ethernet/intel/idpf/virtchnl2.h >>> @@ -978,7 +978,7 @@ struct virtchnl2_ptype { >>> u8 proto_id_count; >>> __le16 pad; >>> __le16 proto_id[]; >>> -}; >>> +} __packed; >>> VIRTCHNL2_CHECK_STRUCT_LEN(6, virtchnl2_ptype); >>> /** >> >> Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de> >> >> >> >> Kind regards, >> >> Paul >
diff --git a/drivers/net/ethernet/intel/idpf/virtchnl2.h b/drivers/net/ethernet/intel/idpf/virtchnl2.h index 8dc83788972..dd750e6dcd0 100644 --- a/drivers/net/ethernet/intel/idpf/virtchnl2.h +++ b/drivers/net/ethernet/intel/idpf/virtchnl2.h @@ -978,7 +978,7 @@ struct virtchnl2_ptype { u8 proto_id_count; __le16 pad; __le16 proto_id[]; -}; +} __packed; VIRTCHNL2_CHECK_STRUCT_LEN(6, virtchnl2_ptype); /**
Config option in arm random config file is causing the compiler to add padding. Avoid it by using "__packed" structure attribute for virtchnl2_ptype struct. Fixes: 0d7502a9b4a7 ("virtchnl: add virtchnl version 2 ops") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202312220250.ufEm8doQ-lkp@intel.com Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com> Signed-off-by: Pavan Kumar Linga <pavan.kumar.linga@intel.com> --- drivers/net/ethernet/intel/idpf/virtchnl2.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)