The main aim of this patchset is to fix the bug reported in https://bugs.launchpad.net/qemu/+bug/1756927 where we don't report the correct FSR when a BKPT instruction causes us to take an exception to AArch32 with LPAE enabled. The other patches fix some minor bugs found along the way:
* we weren't honouring MDCR_EL2.TDE when delivering an exception caused by a BRK or BKPT insn, so we'd always send it to EL1 even if it should have gone to EL2 * our logic to decide whether to report a short-format or long-format LPAE for hardware breakpoint and watchpoint exceptions would get it wrong in some corner cases: we could select the short format because we're at EL0 and the EL1 translation regime is not using LPAE, but then route the debug exception to EL2 because of MDCR_EL2.TDE and hand EL2 the wrong format FSR. * when taking a debug exception in AArch32, we would set the guest visible IFAR to whatever old value was lying around in env->exception.vaddress. IFAR in this situation is architecturally UNKNOWN, but letting it be possibly set to an old value that the guest shouldn't be able to see at its current security/exception level is not permitted, and setting it to a non-deterministic value is bad for record-and-replay. (This patchset further reduces the set of places that are calling the somewhat dubious extended_addresses_enabled() function. The last callsite is in the CONTEXTIDR write function, and that should probably be updated something along the lines of the ideas I wrote in this email last year: https://www.mail-archive.com/qemu-devel@nongnu.org/msg491671.html but that is a cleanup for another day.) thanks -- PMM Peter Maydell (4): target/arm: Honour MDCR_EL2.TDE when routing exceptions due to BKPT/BRK target/arm: Factor out code to calculate FSR for debug exceptions target/arm: Set FSR for BKPT, BRK when raising exception target/arm: Always set FAR to a known unknown value for debug exceptions target/arm/helper.h | 1 + target/arm/internals.h | 25 +++++++++++++++++++++++++ target/arm/helper.c | 1 - target/arm/op_helper.c | 33 ++++++++++++++++++++++----------- target/arm/translate-a64.c | 15 +++++++++++++-- target/arm/translate.c | 19 ++++++++++++++----- 6 files changed, 75 insertions(+), 19 deletions(-) -- 2.16.2
