On Sat, May 4, 2019 at 8:38 PM Karsten Merker <mer...@debian.org> wrote: > > On Sat, May 04, 2019 at 09:24:15AM +0530, Anup Patel wrote: > > [U-Boot+OpenSBI crash with more than 2GB RAM in qemu-system-riscv64] > > I tried again with image header changes applied to u-boot and > > Linux kernel but still not able to reproduce the issues. > > > > Either you might have more local changes or debian toolchain > > is causing issue for u-boot. > > Hello, > > I hadn't made any local changes besides the ones described in my > original email, i.e. the application of the booti patches. To > check for a toolchain-related problem I have rebuilt everything > with both the gcc8-based and the gcc7-based buildroot toolchains, > but the problem remained in all cases, regardless of whether I > used the branch with the booti patch or the plain v2019.07-rc1 > tag, so the problem is definitely not specific to the Debian > toolchain. As a new qemu release has happend just a few days > ago, I have now tried to upgrade qemu from the previous release > version 3.1.0 to the freshly released version 4.0.0, and indeed > with qemu 4.0.0 both the 2GB problem and the hang of init in SMP > configurations with OpenSBI+U-Boot are gone. Which qemu version > had you been using in your tests?
I am using QEMU 4.0.0-rc2. Like mentioned in previous email, BBL has limitation that it allows full memory access to S-mode software. This means S-mode software can actually corrupt BBL too. This is not possible in OpenSBI because we use PMP configuration to protect firmware and critical memory regions. With QEMU 3.x, OpenSBI+U-Boot is failing for you because there were bugs in QEMU PMP checks. > > What makes this interesting is that I'm running qemu 3.1.0 with > BBL and Linux in a 4-core SMP configuration and with 8GB of RAM > since months and never had any problems with it, so > OpenSBI+U-Boot seems to do something differently from BBL. That's because BBL is buggy. It allows complete RAM access to S-mode software so QEMU PMP checks did not matter. Regards, Anup _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
