On 2/15/23 10:59, Daniel Henrique Barboza wrote:
+ mem = probe_access(env, address, cbozlen, MMU_DATA_STORE,
+ cpu_mmu_index(env, false), ra);
+
+ /* Zero the block */
+ memset(mem, 0, cbozlen);
Will crash if address does not resolve to ram.
According to page 16, you need to store zeros even if the memory is not cacheable. C.f.
target/arm/helper-a64.c HELPER(dc_zva) or target/s390x/tcg/mem_helper.c do_access_memset.
While re-reading the ARM code, I remembered that the ARM dc.zva instruction is required to
produce original unmasked address on a page fault, thus the little dance with two calls to
probe_write.
I don't immediately see language in the risc-v spec beyond "CMO instructions do not
generate address misaligned exceptions."
r~
