[Qemu-commits] [qemu/qemu] 987a23: target/arm: Deliver BKPT/BRK exceptions to correct...

[Peter Maydell]

  Branch: refs/heads/master
  Home:   https://github.com/qemu/qemu
  Commit: 987a23224218fa3bb3aa0024ad236dcf29ebde9e
      
https://github.com/qemu/qemu/commit/987a23224218fa3bb3aa0024ad236dcf29ebde9e
  Author: Peter Maydell <address@hidden>
  Date:   2019-07-30 (Tue, 30 Jul 2019)

  Changed paths:
    M target/arm/op_helper.c

  Log Message:
  -----------
  target/arm: Deliver BKPT/BRK exceptions to correct exception level

Most Arm architectural debug exceptions (eg watchpoints) are ignored
if the configured "debug exception level" is below the current
exception level (so for example EL1 can't arrange to get debug exceptions
for EL2 execution). Exceptions generated by the BRK or BPKT instructions
are a special case -- they must always cause an exception, so if
we're executing above the debug exception level then we
must take them to the current exception level.

This fixes a bug where executing BRK at EL2 could result in an
exception being taken at EL1 (which is strictly forbidden by the
architecture).

Fixes: https://bugs.launchpad.net/qemu/+bug/1838277
Signed-off-by: Peter Maydell <address@hidden>
Reviewed-by: Richard Henderson <address@hidden>
Reviewed-by: Philippe Mathieu-Daudé <address@hidden>
Message-id: address@hidden