tree dc88bab6bf1d2a36f887c94f39820a4b12c41c56
parent 5669d26ec614b3f4c56cf1489b9095ed327938b1
author Peter Maydell <peter.maydell@linaro.org> 1721125832 +0100
committer Peter Maydell <peter.maydell@linaro.org> 1721306968 +0100

target/arm: LDAPR should honour SCTLR_ELx.nAA

In commit c1a1f80518d360b when we added the FEAT_LSE2 relaxations to
the alignment requirements for atomic and ordered loads and stores,
we didn't quite get it right for LDAPR/LDAPRH/LDAPRB with no
immediate offset.  These instructions were handled in the old decoder
as part of disas_ldst_atomic(), but unlike all the other insns that
function decoded (LDADD, LDCLR, etc) these insns are "ordered", not
"atomic", so they should be using check_ordered_align() rather than
check_atomic_align().  Commit c1a1f80518d360b used
check_atomic_align() regardless for everything in
disas_ldst_atomic().  We then carried that incorrect check over in
the decodetree conversion, where LDAPR/LDAPRH/LDAPRB are now handled
by trans_LDAPR().

The effect is that when FEAT_LSE2 is implemented, these instructions
don't honour the SCTLR_ELx.nAA bit and will generate alignment
faults when they should not.

(The LDAPR insns with an immediate offset were in disas_ldst_ldapr_stlr()
and then in trans_LDAPR_i() and trans_STLR_i(), and have always used
the correct check_ordered_align().)

Use check_ordered_align() in trans_LDAPR().

Cc: qemu-stable@nongnu.org
Fixes: c1a1f80518d360b ("target/arm: Relax ordered/atomic alignment checks for LSE2")
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20240709134504.3500007-3-peter.maydell@linaro.org