---------- Forwarded message --------- From: Alexandro Sánchez Bach <alexaltea...@gmail.com> Date: Wed, Jan 31, 2018 at 2:29 AM Subject: QEMU: AMD IOMMU implementation bugs To: <davidkiar...@gmail.com>
Hey David, hello Mr Alexandro Sanchez Bach, I'm working with your AMD IOMMU implementation since I'm writing a PlayStation 4 emulator. I found few bugs, that I wanted to report to you. 1. https://github.com/qemu/qemu/blob/master/hw/i386/amd_iommu.c#L380 Did you mean amdvi_assign_orq instead of amdvi_test_mask? Otherwise my guest OS will get stuck in an endless loop waiting for a flag that never comes. it looks like you're correct to me. 2. The arguments `addr` and `val` are swapped in these two lines: > static void amdvi_writeq_raw(AMDVIState *s, uint64_t val, hwaddr addr); > amdvi_writeq_raw(s, addr, amdvi_readq(s, addr) | val); same here. 3. And this might be something specific to my AMD IOMMU (1022:1437, Family 16h), but the PS4 OS is checks the entire word stored in these registers and computes the expression as: config[AMDVI_CAPAB_BAR_LOW] | cap[AMDVI_CAPAB_BAR_HIGH] << 32 So just storing half words should be wrong. not sure about this. since it looks to me like you're working with emulation and virtualization, i have cc'd people who i know/knew to be actively involved. it doubt it would take any effort for these people to respond to bugs like above in the future. Cheers, Alex
