| Message ID | 20180611135223.81865-1-borntraeger@de.ibm.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2,1/1] s390x/ipl: Try to detect Linux vs non Linux for initial IPL PSW | expand |
On 11.06.2018 15:52, Christian Borntraeger wrote: > Right now the IPL device always starts from address 0x10000 (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 <borntraeger@de.ibm.com> > --- > v1->v2: > - use LINUX_MAGIC_ADDR define > - use assert for valid iplpsw pointer > - add endianess conversion > hw/s390x/ipl.c | 15 ++++++++++++++- > 1 file changed, 14 insertions(+), 1 deletion(-) > > diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c > index 04245b5258..3790153fa9 100644 > --- a/hw/s390x/ipl.c > +++ b/hw/s390x/ipl.c > @@ -29,6 +29,7 @@ > #include "exec/exec-all.h" > > #define KERN_IMAGE_START 0x010000UL > +#define LINUX_MAGIC_ADDR 0x010008UL > #define KERN_PARM_AREA 0x010480UL > #define INITRD_START 0x800000UL > #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; > + uint64_t *iplpsw; > + uint64_t pentry; > + char *magic; > int kernel_size; > Error *err = NULL; > > @@ -157,6 +160,16 @@ 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 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 use the IPL PSW */ > + iplpsw = rom_ptr(0); > + assert(iplpsw); > + pentry = be64_to_cpu(*iplpsw) & 0x7fffffffUL; > + } > } > if (kernel_size < 0) { > error_setg(&err, "could not load kernel '%s'", ipl->kernel); > Have you tried this with kvm-unit-tests? (no magic but we rely on 0x10000)
On 11.06.2018 15:56, David Hildenbrand wrote: > On 11.06.2018 15:52, Christian Borntraeger wrote: >> Right now the IPL device always starts from address 0x10000 (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 <borntraeger@de.ibm.com> >> --- >> v1->v2: >> - use LINUX_MAGIC_ADDR define >> - use assert for valid iplpsw pointer >> - add endianess conversion >> hw/s390x/ipl.c | 15 ++++++++++++++- >> 1 file changed, 14 insertions(+), 1 deletion(-) >> >> diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c >> index 04245b5258..3790153fa9 100644 >> --- a/hw/s390x/ipl.c >> +++ b/hw/s390x/ipl.c >> @@ -29,6 +29,7 @@ >> #include "exec/exec-all.h" >> >> #define KERN_IMAGE_START 0x010000UL >> +#define LINUX_MAGIC_ADDR 0x010008UL >> #define KERN_PARM_AREA 0x010480UL >> #define INITRD_START 0x800000UL >> #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; >> + uint64_t *iplpsw; >> + uint64_t pentry; >> + char *magic; >> int kernel_size; >> Error *err = NULL; >> >> @@ -157,6 +160,16 @@ 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 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 use the IPL PSW */ >> + iplpsw = rom_ptr(0); >> + assert(iplpsw); >> + pentry = be64_to_cpu(*iplpsw) & 0x7fffffffUL; >> + } >> } >> if (kernel_size < 0) { >> error_setg(&err, "could not load kernel '%s'", ipl->kernel); >> > > Have you tried this with kvm-unit-tests? (no magic but we rely on 0x10000) kvm-unit-tests are elf files which should be handled by the load_elf() some lines earlier already, so I think we should be fine there, shouldn't we? Thomas
On 11.06.2018 18:11, Thomas Huth wrote: > On 11.06.2018 15:56, David Hildenbrand wrote: >> On 11.06.2018 15:52, Christian Borntraeger wrote: >>> Right now the IPL device always starts from address 0x10000 (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 <borntraeger@de.ibm.com> >>> --- >>> v1->v2: >>> - use LINUX_MAGIC_ADDR define >>> - use assert for valid iplpsw pointer >>> - add endianess conversion >>> hw/s390x/ipl.c | 15 ++++++++++++++- >>> 1 file changed, 14 insertions(+), 1 deletion(-) >>> >>> diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c >>> index 04245b5258..3790153fa9 100644 >>> --- a/hw/s390x/ipl.c >>> +++ b/hw/s390x/ipl.c >>> @@ -29,6 +29,7 @@ >>> #include "exec/exec-all.h" >>> >>> #define KERN_IMAGE_START 0x010000UL >>> +#define LINUX_MAGIC_ADDR 0x010008UL >>> #define KERN_PARM_AREA 0x010480UL >>> #define INITRD_START 0x800000UL >>> #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; >>> + uint64_t *iplpsw; >>> + uint64_t pentry; >>> + char *magic; >>> int kernel_size; >>> Error *err = NULL; >>> >>> @@ -157,6 +160,16 @@ 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 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 use the IPL PSW */ >>> + iplpsw = rom_ptr(0); >>> + assert(iplpsw); >>> + pentry = be64_to_cpu(*iplpsw) & 0x7fffffffUL; >>> + } >>> } >>> if (kernel_size < 0) { >>> error_setg(&err, "could not load kernel '%s'", ipl->kernel); >>> >> >> Have you tried this with kvm-unit-tests? (no magic but we rely on 0x10000) > > kvm-unit-tests are elf files which should be handled by the load_elf() > some lines earlier already, so I think we should be fine there, > shouldn't we? Indeed, this should work. > > Thomas > >
On 11.06.2018 15:52, Christian Borntraeger wrote: > Right now the IPL device always starts from address 0x10000 (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 <borntraeger@de.ibm.com> > --- > v1->v2: > - use LINUX_MAGIC_ADDR define > - use assert for valid iplpsw pointer > - add endianess conversion > hw/s390x/ipl.c | 15 ++++++++++++++- > 1 file changed, 14 insertions(+), 1 deletion(-) > > diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c > index 04245b5258..3790153fa9 100644 > --- a/hw/s390x/ipl.c > +++ b/hw/s390x/ipl.c > @@ -29,6 +29,7 @@ > #include "exec/exec-all.h" > > #define KERN_IMAGE_START 0x010000UL > +#define LINUX_MAGIC_ADDR 0x010008UL > #define KERN_PARM_AREA 0x010480UL > #define INITRD_START 0x800000UL > #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; > + uint64_t *iplpsw; > + uint64_t pentry; > + char *magic; > int kernel_size; > Error *err = NULL; > > @@ -157,6 +160,16 @@ 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 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 use the IPL PSW */ > + iplpsw = rom_ptr(0); > + assert(iplpsw); > + pentry = be64_to_cpu(*iplpsw) & 0x7fffffffUL; > + } > } > if (kernel_size < 0) { > error_setg(&err, "could not load kernel '%s'", ipl->kernel); Reviewed-by: Thomas Huth <thuth@redhat.com>
On 11.06.2018 15:52, Christian Borntraeger wrote: > Right now the IPL device always starts from address 0x10000 (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 <borntraeger@de.ibm.com> > --- > v1->v2: > - use LINUX_MAGIC_ADDR define > - use assert for valid iplpsw pointer > - add endianess conversion > hw/s390x/ipl.c | 15 ++++++++++++++- > 1 file changed, 14 insertions(+), 1 deletion(-) > > diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c > index 04245b5258..3790153fa9 100644 > --- a/hw/s390x/ipl.c > +++ b/hw/s390x/ipl.c > @@ -29,6 +29,7 @@ > #include "exec/exec-all.h" > > #define KERN_IMAGE_START 0x010000UL > +#define LINUX_MAGIC_ADDR 0x010008UL > #define KERN_PARM_AREA 0x010480UL > #define INITRD_START 0x800000UL > #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; > + uint64_t *iplpsw; > + uint64_t pentry; > + char *magic; > int kernel_size; > Error *err = NULL; > > @@ -157,6 +160,16 @@ 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 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 use the IPL PSW */ > + iplpsw = rom_ptr(0); > + assert(iplpsw); Hmm, wait, what if load_image_targphys() failed and returned a kernel_size < 0 ... won't we hit that assert() in that case? I think you might want to check for kernel_size > 0 (or even > 8) here first. > + pentry = be64_to_cpu(*iplpsw) & 0x7fffffffUL; > + } > } > if (kernel_size < 0) { > error_setg(&err, "could not load kernel '%s'", ipl->kernel); > Thomas
On 06/11/2018 06:16 PM, Thomas Huth wrote: > On 11.06.2018 15:52, Christian Borntraeger wrote: >> Right now the IPL device always starts from address 0x10000 (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 <borntraeger@de.ibm.com> >> --- >> v1->v2: >> - use LINUX_MAGIC_ADDR define >> - use assert for valid iplpsw pointer >> - add endianess conversion >> hw/s390x/ipl.c | 15 ++++++++++++++- >> 1 file changed, 14 insertions(+), 1 deletion(-) >> >> diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c >> index 04245b5258..3790153fa9 100644 >> --- a/hw/s390x/ipl.c >> +++ b/hw/s390x/ipl.c >> @@ -29,6 +29,7 @@ >> #include "exec/exec-all.h" >> >> #define KERN_IMAGE_START 0x010000UL >> +#define LINUX_MAGIC_ADDR 0x010008UL >> #define KERN_PARM_AREA 0x010480UL >> #define INITRD_START 0x800000UL >> #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; >> + uint64_t *iplpsw; >> + uint64_t pentry; >> + char *magic; >> int kernel_size; >> Error *err = NULL; >> >> @@ -157,6 +160,16 @@ 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 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 use the IPL PSW */ >> + iplpsw = rom_ptr(0); >> + assert(iplpsw); > > Hmm, wait, what if load_image_targphys() failed and returned a > kernel_size < 0 ... won't we hit that assert() in that case? I think you > might want to check for kernel_size > 0 (or even > 8) here first. Yes you are right. > >> + pentry = be64_to_cpu(*iplpsw) & 0x7fffffffUL; This is also not proper. the IPL PSW is more or less an ESA (31bit) PSW. So I rather need to get the 4 byte address part from location 4 (and only do a byteswap there). >> + } >> } >> if (kernel_size < 0) { >> error_setg(&err, "could not load kernel '%s'", ipl->kernel); >> > > Thomas >
On 06/11/2018 06:16 PM, Thomas Huth wrote: > On 11.06.2018 15:52, Christian Borntraeger wrote: >> Right now the IPL device always starts from address 0x10000 (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 <borntraeger@de.ibm.com> >> --- >> v1->v2: >> - use LINUX_MAGIC_ADDR define >> - use assert for valid iplpsw pointer >> - add endianess conversion >> hw/s390x/ipl.c | 15 ++++++++++++++- >> 1 file changed, 14 insertions(+), 1 deletion(-) >> >> diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c >> index 04245b5258..3790153fa9 100644 >> --- a/hw/s390x/ipl.c >> +++ b/hw/s390x/ipl.c >> @@ -29,6 +29,7 @@ >> #include "exec/exec-all.h" >> >> #define KERN_IMAGE_START 0x010000UL >> +#define LINUX_MAGIC_ADDR 0x010008UL >> #define KERN_PARM_AREA 0x010480UL >> #define INITRD_START 0x800000UL >> #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; >> + uint64_t *iplpsw; >> + uint64_t pentry; >> + char *magic; >> int kernel_size; >> Error *err = NULL; >> >> @@ -157,6 +160,16 @@ 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 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 use the IPL PSW */ >> + iplpsw = rom_ptr(0); >> + assert(iplpsw); > > Hmm, wait, what if load_image_targphys() failed and returned a > kernel_size < 0 ... won't we hit that assert() in that case? I think you > might want to check for kernel_size > 0 (or even > 8) here first. I think I can just check for iplpsw being != NULL. That will only be the case if the load has succeeded.
diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c index 04245b5258..3790153fa9 100644 --- a/hw/s390x/ipl.c +++ b/hw/s390x/ipl.c @@ -29,6 +29,7 @@ #include "exec/exec-all.h" #define KERN_IMAGE_START 0x010000UL +#define LINUX_MAGIC_ADDR 0x010008UL #define KERN_PARM_AREA 0x010480UL #define INITRD_START 0x800000UL #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; + uint64_t *iplpsw; + uint64_t pentry; + char *magic; int kernel_size; Error *err = NULL; @@ -157,6 +160,16 @@ 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 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 use the IPL PSW */ + iplpsw = rom_ptr(0); + assert(iplpsw); + pentry = be64_to_cpu(*iplpsw) & 0x7fffffffUL; + } } if (kernel_size < 0) { error_setg(&err, "could not load kernel '%s'", ipl->kernel);
Right now the IPL device always starts from address 0x10000 (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 <borntraeger@de.ibm.com> --- v1->v2: - use LINUX_MAGIC_ADDR define - use assert for valid iplpsw pointer - add endianess conversion hw/s390x/ipl.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-)