On 12.06.2018 14:59, Christian Borntraeger wrote:
> Right now the IPL device always starts from address 0x1 (the usual
> Linux entry point). To run other guests (e.g. test programs) it is
> useful to use the IPL PSW from address 0. We can use the Linux magic
> at 0x10008 to decide.
>
> Signed-off-by: Christian Borntraeger
> ---
> v3->v4:
> - iplpsw-> ipl_psw
> - move check for load failures into the non-elf case
> - change comment about ipl psw
> v2->v3:
> - check for iplpsw to avoid assert on file errors
> - use 4 bytes at 4 instead of 8 bytes at 0
> v1->v2:
> - use LINUX_MAGIC_ADDR define
> - use assert for valid iplpsw pointer
> - add endianess conversion
> hw/s390x/ipl.c | 27 ++-
> 1 file changed, 22 insertions(+), 5 deletions(-)
>
> diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c
> index 04245b5258..0d67349004 100644
> --- a/hw/s390x/ipl.c
> +++ b/hw/s390x/ipl.c
> @@ -29,6 +29,7 @@
> #include "exec/exec-all.h"
>
> #define KERN_IMAGE_START0x01UL
> +#define LINUX_MAGIC_ADDR0x010008UL
> #define KERN_PARM_AREA 0x010480UL
> #define INITRD_START0x80UL
> #define INITRD_PARM_START 0x010408UL
> @@ -105,7 +106,9 @@ static uint64_t bios_translate_addr(void *opaque,
> uint64_t srcaddr)
> static void s390_ipl_realize(DeviceState *dev, Error **errp)
> {
> S390IPLState *ipl = S390_IPL(dev);
> -uint64_t pentry = KERN_IMAGE_START;
> +uint32_t *ipl_psw;
> +uint64_t pentry;
> +char *magic;
> int kernel_size;
> Error *err = NULL;
>
> @@ -157,10 +160,24 @@ static void s390_ipl_realize(DeviceState *dev, Error
> **errp)
> NULL, 1, EM_S390, 0, 0);
> if (kernel_size < 0) {
> kernel_size = load_image_targphys(ipl->kernel, 0, ram_size);
> -}
> -if (kernel_size < 0) {
> -error_setg(, "could not load kernel '%s'", ipl->kernel);
> -goto error;
> +if (kernel_size < 0) {
> +error_setg(, "could not load kernel '%s'", ipl->kernel);
> +goto error;
> +}
> +/* if this is Linux use KERN_IMAGE_START */
> +magic = rom_ptr(LINUX_MAGIC_ADDR);
> +if (magic && !memcmp(magic, "S390EP", 6)) {
> +pentry = KERN_IMAGE_START;
> +} else {
> +/* if not Linux load the address of the (short) IPL PSW */
> +ipl_psw = rom_ptr(4);
> +if (ipl_psw) {
> +pentry = be32_to_cpu(*ipl_psw) & 0x7fffUL;
> +} else {
> +error_setg(, "Could not get IPL PSW");
> +goto error;
> +}
> +}
Reviewed-by: David Hildenbrand
> }
> /*
> * Is it a Linux kernel (starting at 0x1)? If yes, we fill in the
>
--
Thanks,
David / dhildenb
