From d139786e1b3d67991e6cb49a8a59bb2182350285 Mon Sep 17 00:00:00 2001 From: Daniel Henrique Barboza Date: Wed, 10 Nov 2021 17:25:16 -0300 Subject: ppc/mmu_helper.c: do not truncate 'ea' in booke206_invalidate_ea_tlb() 'tlbivax' is implemented by gen_tlbivax_booke206() via gen_helper_booke206_tlbivax(). In case the TLB needs to be flushed, booke206_invalidate_ea_tlb() is called. All these functions, but booke206_invalidate_ea_tlb(), uses a 64-bit effective address 'ea'. booke206_invalidate_ea_tlb() uses an uint32_t 'ea' argument that truncates the original 'ea' value for apparently no particular reason. This function retrieves the tlb pointer by calling booke206_get_tlbm(), which also uses a target_ulong address as parameter - in this case, a truncated 'ea' address. All the surrounding logic considers the effective TLB address as a 64 bit value, aside from the signature of booke206_invalidate_ea_tlb(). Last but not the least, PowerISA 2.07B section 6.11.4.9 [2] makes it clear that the effective address "EA" is a 64 bit value. Commit 01662f3e5133 introduced this code and no changes were made ever since. An user detected a problem with tlbivax [1] stating that this address truncation was the cause. This same behavior might be the source of several subtle bugs that were never caught. For all these reasons, this patch assumes that this address truncation is the result of a mistake/oversight of the original commit, and changes booke206_invalidate_ea_tlb() 'ea' argument to 'vaddr'. [1] https://gitlab.com/qemu-project/qemu/-/issues/52 [2] https://wiki.raptorcs.com/wiki/File:PowerISA_V2.07B.pdf Fixes: 01662f3e5133 ("PPC: Implement e500 (FSL) MMU") Resolves: https://gitlab.com/qemu-project/qemu/-/issues/52 Signed-off-by: Daniel Henrique Barboza Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Cédric Le Goater --- target/ppc/mmu_helper.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'target/ppc/mmu_helper.c') diff --git a/target/ppc/mmu_helper.c b/target/ppc/mmu_helper.c index 2cb98c5169..e0c4950dda 100644 --- a/target/ppc/mmu_helper.c +++ b/target/ppc/mmu_helper.c @@ -1216,7 +1216,7 @@ void helper_booke206_tlbsx(CPUPPCState *env, target_ulong address) } static inline void booke206_invalidate_ea_tlb(CPUPPCState *env, int tlbn, - uint32_t ea) + vaddr ea) { int i; int ways = booke206_tlb_ways(env, tlbn); -- cgit v1.2.3-55-g7522