Ard, Let's see if we can remove the ESRT access from those paths. That would be the better fix.
Thanks, Mike > -----Original Message----- > From: devel@edk2.groups.io > [mailto:devel@edk2.groups.io] On Behalf Of Ard > Biesheuvel > Sent: Friday, April 19, 2019 11:11 AM > To: Kinney, Michael D <michael.d.kin...@intel.com> > Cc: devel@edk2.groups.io; ming.hu...@linaro.org; Wu, > Hao A <hao.a...@intel.com>; Wang, Jian J > <jian.j.w...@intel.com> > Subject: Re: [edk2-devel] [PATCH resend] > MdeModulePkg/EsrtDxe: allocate ESRT table from > RtServicesData memory > > On Fri, 19 Apr 2019 at 20:08, Kinney, Michael D > <michael.d.kin...@intel.com> wrote: > > > > Ard, > > > > Where is the use of ESRT at runtime? > > > > DxeCapsuleLibFmp is invoked at runtime by the > UpdateCapsule() and > QueryCapsuleCapabilities() code. > > The Canonical FWTS crashes on this runtime service on > some ARM and x86 > systems due to this issue, hence the patch. > > > > The SetVa conversion of the ESRT table may be an old > artifact > > that we should consider removing. > > > > No, it is definitely live code. > > > > > > > -----Original Message----- > > > From: devel@edk2.groups.io > > > [mailto:devel@edk2.groups.io] On Behalf Of Ard > > > Biesheuvel > > > Sent: Friday, April 19, 2019 10:54 AM > > > To: edk2-devel-groups-io <devel@edk2.groups.io>; > > > Kinney, Michael D <michael.d.kin...@intel.com> > > > Cc: ming.hu...@linaro.org; Wu, Hao A > > > <hao.a...@intel.com>; Wang, Jian J > > > <jian.j.w...@intel.com> > > > Subject: Re: [edk2-devel] [PATCH resend] > > > MdeModulePkg/EsrtDxe: allocate ESRT table from > > > RtServicesData memory > > > > > > On Fri, 19 Apr 2019 at 19:42, Ard Biesheuvel > > > <ard.biesheu...@linaro.org> wrote: > > > > > > > > On Fri, 19 Apr 2019 at 19:36, Michael D Kinney > > > > <michael.d.kin...@intel.com> wrote: > > > > > > > > > > Hi Ard, > > > > > > > > > > The UEFI Specification Section 23.3 says: > > > > > > > > > > "The ESRT shall be stored in memory of > type > > > EfiBootServicesData." > > > > > > > > > > If an RT driver needs ESRT info after > > > ExitBootServices(), then the > > > > > RT driver should collect that information > before > > > ExitBootServices(). > > > > > > > > > > > > > But that means that before EBS(), we will have to > > > make a copy of the > > > > ESRT into runtime services data, and we will end > up > > > using twice as > > > > much memory - one copy in boot services data for > the > > > OS, and one copy > > > > in runtime services data for the firmware itself. > I > > > understand the > > > > reasoning behind preferring boot over runtime, so > > > that the OS is not > > > > burdened with it if it does not care. But it this > > > case, the RT > > > > services data will be allocated regardless, and > so we > > > end up using > > > > less memory if we expose that same copy to the > OS. > > > > > > > > > > Actually, DxeCapsuleLibVirtualAddressChangeEvent() > in > > > DxeCapsuleLibFmp > > > updates the ESRT pointer to virtual, so this code > is > > > clearly based on > > > the assumption that the ESRT resides in memory that > is > > > covered by a > > > runtime VA mapping. > > > > > > Could we instead clarify the UEFI spec to something > > > like > > > > > > "The ESRT shall be stored in memory of type > > > EfiBootServicesData unless > > > the runtime services implementations themselves > need to > > > access it at > > > OS runtime, in which case it may be stored in > > > EfiRuntimeServicesData." > > > > > > > > > > -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#39332): https://edk2.groups.io/g/devel/message/39332 Mute This Topic: https://groups.io/mt/31245843/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
