On 2019-04-10 09:41:43, Ard Biesheuvel wrote: > On Wed, 10 Apr 2019 at 01:41, Jordan Justen <jordan.l.jus...@intel.com> wrote: > > > > https://github.com/jljusten/edk2.git temp-ram-support-v2 > > > > https://github.com/jljusten/edk2/commits/temp-ram-support-v2 > > > > v2: > > * Add AARCH64 and ARM assembly > > Hi Jordan, > > I'm not sure I'm following the reasoning behind this.
Did you see the explanation in patch 1 commit message? Could you reply there with questions, or maybe I should try to expand on that? > Does this fix an issue we currently have on ARM systems? Yes, but I don't know of a case where it has been observed on AARCH64/ARM. Nevertheless, as far as I can tell, a similar issue could happen because the current implementation relies on non-spec'd behavior of code gen within a C function. (Not the C calling convention, but what code does with inside the function between calls.) > And how did you build and/or test OVMF for ARM? I built ArmVirtPkg for AARCH64 and ARM on x86_64 Linux with a cross-compiler, and ran it with qemu. -Jordan > > > * Drop IA32 and X64 .S source files > > * Adjust PEI_CORE_TEMPORARY_RAM_TRANSITION pointer in the assembly > > code based on the stack pointer change before & after > > TemporaryRamSupport->TemporaryRamMigration > > * Drop extra cleanup patches for OvmfPkg & EmulatorPkg. These were > > just complicating the series. > > > > This series fixes an issue that, while rare, is possible based on the > > way the TemporaryRamSupport PPI is defined along with how it is used > > by the PEI Core. > > > > Liu Yu reported a boot issue with EmulatorPkg, which I believe was > > caused by this issue. > > > > The details of the issue are described in the commit message of the > > "MdeModulePkg/Core/Pei: Add interface for assembly based > > TemporaryRamSupport" patch. > > > > Testing: > > > > I tested building and booting in several scenarios: > > > > * OVMF IA32 & X64 on Linux > > * ArmVirtPkg AARCH64 & ARM on x86_64 Linux > > * EmulatorPkg IA32 & X64 on Linux > > > > Untested: > > > > * My system does not reproduce the issue that Liu Yu reported with > > EmulatorPkg, so I can't say that I have verified that issue. > > * Building on windows > > * AARCH64/ARM TemporaryRamMigration.asm sources -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#38834): https://edk2.groups.io/g/devel/message/38834 Mute This Topic: https://groups.io/mt/31016921/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
