| Message ID | 20170516224721.13832-3-aurelien@aurel32.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 05/16/2017 03:47 PM, Aurelien Jarno wrote: > When a masked exception happens, the SH4 CPU generates a non-masked > reset exception, which then jumps to the reset vector at address > 0xA0000000. While this is emulated correctly in QEMU, this does not > work when using a kernel and initrd as this address then contain an > illegal instruction (and there is no guarantee the kernel and initrd > haven't been overwritten). > > Therefore call qemu_system_reset_request to reload the kernel and initrd > and load the program counter to the kernel entry point. > > Signed-off-by: Aurelien Jarno<aurelien@aurel32.net> > --- > target/sh4/helper.c | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) Reviewed-by: Richard Henderson <rth@twiddle.net> r~
diff --git a/target/sh4/helper.c b/target/sh4/helper.c index 4c024f9529..5296e7cf4e 100644 --- a/target/sh4/helper.c +++ b/target/sh4/helper.c @@ -21,6 +21,7 @@ #include "cpu.h" #include "exec/exec-all.h" #include "exec/log.h" +#include "sysemu/sysemu.h" #if !defined(CONFIG_USER_ONLY) #include "hw/sh4/sh_intc.h" @@ -92,7 +93,14 @@ void superh_cpu_do_interrupt(CPUState *cs) if (env->sr & (1u << SR_BL)) { if (do_exp && cs->exception_index != 0x1e0) { - cs->exception_index = 0x000; /* masked exception -> reset */ + /* In theory a masked exception generates a reset exception, + which in turn jumps to the reset vector. However this only + works when using a bootloader. When using a kernel and an + initrd, they need to be reloaded and the program counter + should be loaded with the kernel entry point. + qemu_system_reset_request takes care of that. */ + qemu_system_reset_request(); + return; } if (do_irq && !env->in_sleep) { return; /* masked */
When a masked exception happens, the SH4 CPU generates a non-masked reset exception, which then jumps to the reset vector at address 0xA0000000. While this is emulated correctly in QEMU, this does not work when using a kernel and initrd as this address then contain an illegal instruction (and there is no guarantee the kernel and initrd haven't been overwritten). Therefore call qemu_system_reset_request to reload the kernel and initrd and load the program counter to the kernel entry point. Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> --- target/sh4/helper.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)