On 11/17/20 7:56 AM, Peter Maydell wrote: > The Linux kernel doesn't use the official bkpt insn for breakpoints; > instead it uses three instructions in the guaranteed-to-UNDEF space, > and generates SIGTRAP for these rather than the SIGILL that most > UNDEF insns generate: > > https://elixir.bootlin.com/linux/v5.9.8/source/arch/arm/kernel/ptrace.c#L197 > > Make QEMU treat these insns specially too. The main benefit of this > is that if you're running a debugger on a guest program that runs > into a GCC __builtin_trap() or LLVM "trap because execution should > never reach here" then you'll get the expected signal rather than a > SIGILL. > > Signed-off-by: Peter Maydell <[email protected]> > --- > This is not a "fix" for LP:1904210, but it does bring QEMU's > behaviour into line with that of the real kernel on that binary.
Reviewed-by: Richard Henderson <[email protected]> r~
