diff options
Diffstat (limited to 'results/scraper/launchpad-without-comments/1879587')
| -rw-r--r-- | results/scraper/launchpad-without-comments/1879587 | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/results/scraper/launchpad-without-comments/1879587 b/results/scraper/launchpad-without-comments/1879587 new file mode 100644 index 00000000..e2c2c0bb --- /dev/null +++ b/results/scraper/launchpad-without-comments/1879587 @@ -0,0 +1,20 @@ +Register number in ESR is incorrect for certain banked registers when switching from AA32 to AA64 + +I am running into a situation where I have: +- A hypervisor running in EL2, AA64 +- A guest running in EL1, AA32 + +We trap certain accesses to special registers such as DACR (via HCR.TVM). One instruction that is trapped is: + +ee03ef10 -> mcr 15, 0, lr, cr3, cr0, {0} + +The guest is running in SVC mode. So, LR should refer to LR_svc there. LR_svc is mapped to X18 in AA64. So, ESR should reflect that. However, the actual ESR value is: 0xfe00dc0 + +If we decode the 'rt': +>>> (0xfe00dc0 >> 5) & 0x1f +14 + +My understanding is that 14 is incorrect in the context of AA64. rt should be set to 18. The current mode being SVC, LR refers to LR_svc not LR_usr. In other words, the mapping between registers in AA64 and AA32 doesn't seem to be accounted for. I've tested this with Qemu 5.0.0 + +Let me know if that makes sense and if you would like more info. I am also happy to test patches. +Thanks for all the great work on Qemu! \ No newline at end of file |