* Ard Biesheuvel <ardb@xxxxxxxxxx> [200226 16:58]: > While making changes to the EFI stub startup code, I noticed that we are > still doing set/way maintenance on the caches when booting on v7 cores. > This works today on VMs by virtue of the fact that KVM traps set/way ops > and cleans the whole address space by VA on behalf of the guest, and on > most v7 hardware, the set/way ops are in fact sufficient when only one > core is running, as there usually is no system cache. But on systems > like SynQuacer, for which 32-bit firmware is available, the current cache > maintenance only pushes the data out to the L3 system cache, where it > is not visible to the CPU once it turns the MMU and caches off. > > So instead, switch to the by-VA cache maintenance that the architecture > requires for v7 and later (and ARM1176, as a side effect). > > Changes since v3: > - ensure that the region that is cleaned after self-relocation of the zImage > covers the appended DTB, if present I gave these a try on top of the earlier "arm: fix Kbuild issue caused by per-task stack protector GCC plugin" and booting still works for me on armv7 including appended dtb: Tested-by: Tony Lindgren <tony@xxxxxxxxxxx>
