| Message ID | 20211122112909.18138-1-mhartmay@linux.ibm.com |
|---|---|
| State | New |
| Headers | show |
| Series | s390x/ipl: support extended kernel command line size | expand |
On 22.11.21 12:29, Marc Hartmayer wrote: > In the past s390 used a fixed command line length of 896 bytes. This has changed > with the Linux commit 5ecb2da660ab ("s390: support command lines longer than 896 > bytes"). There is now a parm area indicating the maximum command line size. This > parm area has always been initialized to zero, so with older kernels this field > would read zero and we must then assume that only 896 bytes are available. > > Acked-by: Viktor Mihajlovski <mihajlov@de.ibm.com> > Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com> > --- > hw/s390x/ipl.c | 23 ++++++++++++++++++++--- > 1 file changed, 20 insertions(+), 3 deletions(-) > > diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c > index 7ddca0127fc2..092c66b3f9f1 100644 > --- a/hw/s390x/ipl.c > +++ b/hw/s390x/ipl.c > @@ -37,8 +37,9 @@ > > #define KERN_IMAGE_START 0x010000UL > #define LINUX_MAGIC_ADDR 0x010008UL > +#define KERN_PARM_AREA_SIZE_ADDR 0x010430UL > #define KERN_PARM_AREA 0x010480UL > -#define KERN_PARM_AREA_SIZE 0x000380UL > +#define LEGACY_KERN_PARM_AREA_SIZE 0x000380UL > #define INITRD_START 0x800000UL > #define INITRD_PARM_START 0x010408UL > #define PARMFILE_START 0x001000UL > @@ -110,6 +111,21 @@ static uint64_t bios_translate_addr(void *opaque, uint64_t srcaddr) > return srcaddr + dstaddr; > } > > +static uint64_t get_max_kernel_cmdline_size(void) > +{ > + uint64_t *size_ptr = rom_ptr(KERN_PARM_AREA_SIZE_ADDR, sizeof(*size_ptr)); > + > + if (size_ptr) { > + uint64_t size; > + > + size = be64_to_cpu(*size_ptr); > + if (size != 0) { Could do "if (size) {" > + return size; > + } > + } > + return LEGACY_KERN_PARM_AREA_SIZE; > +} > + > static void s390_ipl_realize(DeviceState *dev, Error **errp) > { > MachineState *ms = MACHINE(qdev_get_machine()); > @@ -197,10 +213,11 @@ static void s390_ipl_realize(DeviceState *dev, Error **errp) > ipl->start_addr = KERN_IMAGE_START; > /* Overwrite parameters in the kernel image, which are "rom" */ > if (parm_area) { > - if (cmdline_size > KERN_PARM_AREA_SIZE) { > + uint64_t max_cmdline_size = get_max_kernel_cmdline_size(); We might want an empty line here. > + if (cmdline_size > max_cmdline_size) { > error_setg(errp, > "kernel command line exceeds maximum size: %zu > %lu", > - cmdline_size, KERN_PARM_AREA_SIZE); > + cmdline_size, max_cmdline_size); > return; > } > > Reviewed-by: David Hildenbrand <david@redhat.com>
David Hildenbrand <david@redhat.com> writes: > On 22.11.21 12:29, Marc Hartmayer wrote: >> In the past s390 used a fixed command line length of 896 bytes. This has changed >> with the Linux commit 5ecb2da660ab ("s390: support command lines longer than 896 >> bytes"). There is now a parm area indicating the maximum command line size. This >> parm area has always been initialized to zero, so with older kernels this field >> would read zero and we must then assume that only 896 bytes are available. >> >> Acked-by: Viktor Mihajlovski <mihajlov@de.ibm.com> >> Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com> >> --- >> hw/s390x/ipl.c | 23 ++++++++++++++++++++--- >> 1 file changed, 20 insertions(+), 3 deletions(-) >> >> diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c >> index 7ddca0127fc2..092c66b3f9f1 100644 >> --- a/hw/s390x/ipl.c >> +++ b/hw/s390x/ipl.c >> @@ -37,8 +37,9 @@ >> >> #define KERN_IMAGE_START 0x010000UL >> #define LINUX_MAGIC_ADDR 0x010008UL >> +#define KERN_PARM_AREA_SIZE_ADDR 0x010430UL >> #define KERN_PARM_AREA 0x010480UL >> -#define KERN_PARM_AREA_SIZE 0x000380UL >> +#define LEGACY_KERN_PARM_AREA_SIZE 0x000380UL >> #define INITRD_START 0x800000UL >> #define INITRD_PARM_START 0x010408UL >> #define PARMFILE_START 0x001000UL >> @@ -110,6 +111,21 @@ static uint64_t bios_translate_addr(void *opaque, uint64_t srcaddr) >> return srcaddr + dstaddr; >> } >> >> +static uint64_t get_max_kernel_cmdline_size(void) >> +{ >> + uint64_t *size_ptr = rom_ptr(KERN_PARM_AREA_SIZE_ADDR, sizeof(*size_ptr)); >> + >> + if (size_ptr) { >> + uint64_t size; >> + >> + size = be64_to_cpu(*size_ptr); >> + if (size != 0) { > > Could do "if (size) {" Ok. > >> + return size; >> + } >> + } >> + return LEGACY_KERN_PARM_AREA_SIZE; >> +} >> + >> static void s390_ipl_realize(DeviceState *dev, Error **errp) >> { >> MachineState *ms = MACHINE(qdev_get_machine()); >> @@ -197,10 +213,11 @@ static void s390_ipl_realize(DeviceState *dev, Error **errp) >> ipl->start_addr = KERN_IMAGE_START; >> /* Overwrite parameters in the kernel image, which are "rom" */ >> if (parm_area) { >> - if (cmdline_size > KERN_PARM_AREA_SIZE) { >> + uint64_t max_cmdline_size = get_max_kernel_cmdline_size(); > > We might want an empty line here. Yep. > >> + if (cmdline_size > max_cmdline_size) { >> error_setg(errp, >> "kernel command line exceeds maximum size: %zu > %lu", >> - cmdline_size, KERN_PARM_AREA_SIZE); >> + cmdline_size, max_cmdline_size); >> return; >> } >> >> > > Reviewed-by: David Hildenbrand <david@redhat.com> Thanks for the review! > > -- > Thanks, > > David / dhildenb >
Am 22.11.21 um 12:29 schrieb Marc Hartmayer: > In the past s390 used a fixed command line length of 896 bytes. This has changed > with the Linux commit 5ecb2da660ab ("s390: support command lines longer than 896 > bytes"). There is now a parm area indicating the maximum command line size. This > parm area has always been initialized to zero, so with older kernels this field > would read zero and we must then assume that only 896 bytes are available. > > Acked-by: Viktor Mihajlovski <mihajlov@de.ibm.com> > Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> > --- > hw/s390x/ipl.c | 23 ++++++++++++++++++++--- > 1 file changed, 20 insertions(+), 3 deletions(-) > > diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c > index 7ddca0127fc2..092c66b3f9f1 100644 > --- a/hw/s390x/ipl.c > +++ b/hw/s390x/ipl.c > @@ -37,8 +37,9 @@ > > #define KERN_IMAGE_START 0x010000UL > #define LINUX_MAGIC_ADDR 0x010008UL > +#define KERN_PARM_AREA_SIZE_ADDR 0x010430UL > #define KERN_PARM_AREA 0x010480UL > -#define KERN_PARM_AREA_SIZE 0x000380UL > +#define LEGACY_KERN_PARM_AREA_SIZE 0x000380UL > #define INITRD_START 0x800000UL > #define INITRD_PARM_START 0x010408UL > #define PARMFILE_START 0x001000UL > @@ -110,6 +111,21 @@ static uint64_t bios_translate_addr(void *opaque, uint64_t srcaddr) > return srcaddr + dstaddr; > } > > +static uint64_t get_max_kernel_cmdline_size(void) > +{ > + uint64_t *size_ptr = rom_ptr(KERN_PARM_AREA_SIZE_ADDR, sizeof(*size_ptr)); > + > + if (size_ptr) { > + uint64_t size; > + > + size = be64_to_cpu(*size_ptr); > + if (size != 0) { > + return size; > + } > + } > + return LEGACY_KERN_PARM_AREA_SIZE; > +} > + > static void s390_ipl_realize(DeviceState *dev, Error **errp) > { > MachineState *ms = MACHINE(qdev_get_machine()); > @@ -197,10 +213,11 @@ static void s390_ipl_realize(DeviceState *dev, Error **errp) > ipl->start_addr = KERN_IMAGE_START; > /* Overwrite parameters in the kernel image, which are "rom" */ > if (parm_area) { > - if (cmdline_size > KERN_PARM_AREA_SIZE) { > + uint64_t max_cmdline_size = get_max_kernel_cmdline_size(); > + if (cmdline_size > max_cmdline_size) { > error_setg(errp, > "kernel command line exceeds maximum size: %zu > %lu", > - cmdline_size, KERN_PARM_AREA_SIZE); > + cmdline_size, max_cmdline_size); > return; > } > >
On 22/11/2021 12.29, Marc Hartmayer wrote: > In the past s390 used a fixed command line length of 896 bytes. This has changed > with the Linux commit 5ecb2da660ab ("s390: support command lines longer than 896 > bytes"). There is now a parm area indicating the maximum command line size. This > parm area has always been initialized to zero, so with older kernels this field > would read zero and we must then assume that only 896 bytes are available. > > Acked-by: Viktor Mihajlovski <mihajlov@de.ibm.com> > Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com> > --- > hw/s390x/ipl.c | 23 ++++++++++++++++++++--- > 1 file changed, 20 insertions(+), 3 deletions(-) > > diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c > index 7ddca0127fc2..092c66b3f9f1 100644 > --- a/hw/s390x/ipl.c > +++ b/hw/s390x/ipl.c > @@ -37,8 +37,9 @@ > > #define KERN_IMAGE_START 0x010000UL > #define LINUX_MAGIC_ADDR 0x010008UL > +#define KERN_PARM_AREA_SIZE_ADDR 0x010430UL > #define KERN_PARM_AREA 0x010480UL > -#define KERN_PARM_AREA_SIZE 0x000380UL > +#define LEGACY_KERN_PARM_AREA_SIZE 0x000380UL > #define INITRD_START 0x800000UL > #define INITRD_PARM_START 0x010408UL > #define PARMFILE_START 0x001000UL > @@ -110,6 +111,21 @@ static uint64_t bios_translate_addr(void *opaque, uint64_t srcaddr) > return srcaddr + dstaddr; > } > > +static uint64_t get_max_kernel_cmdline_size(void) > +{ > + uint64_t *size_ptr = rom_ptr(KERN_PARM_AREA_SIZE_ADDR, sizeof(*size_ptr)); > + > + if (size_ptr) { > + uint64_t size; > + > + size = be64_to_cpu(*size_ptr); > + if (size != 0) { > + return size; > + } > + } > + return LEGACY_KERN_PARM_AREA_SIZE; > +} > + > static void s390_ipl_realize(DeviceState *dev, Error **errp) > { > MachineState *ms = MACHINE(qdev_get_machine()); > @@ -197,10 +213,11 @@ static void s390_ipl_realize(DeviceState *dev, Error **errp) > ipl->start_addr = KERN_IMAGE_START; > /* Overwrite parameters in the kernel image, which are "rom" */ > if (parm_area) { > - if (cmdline_size > KERN_PARM_AREA_SIZE) { > + uint64_t max_cmdline_size = get_max_kernel_cmdline_size(); > + if (cmdline_size > max_cmdline_size) { > error_setg(errp, > "kernel command line exceeds maximum size: %zu > %lu", I think the %lu likely needs to be turned into a PRIu64 now ... could you please try compiling on a 32-bit host env (e.g. via gitlab-ci), fix the patch accordingly (also with the cosmetics mentioned by David) and send a v2? Thanks! Thomas > - cmdline_size, KERN_PARM_AREA_SIZE); > + cmdline_size, max_cmdline_size); > return; > }
diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c index 7ddca0127fc2..092c66b3f9f1 100644 --- a/hw/s390x/ipl.c +++ b/hw/s390x/ipl.c @@ -37,8 +37,9 @@ #define KERN_IMAGE_START 0x010000UL #define LINUX_MAGIC_ADDR 0x010008UL +#define KERN_PARM_AREA_SIZE_ADDR 0x010430UL #define KERN_PARM_AREA 0x010480UL -#define KERN_PARM_AREA_SIZE 0x000380UL +#define LEGACY_KERN_PARM_AREA_SIZE 0x000380UL #define INITRD_START 0x800000UL #define INITRD_PARM_START 0x010408UL #define PARMFILE_START 0x001000UL @@ -110,6 +111,21 @@ static uint64_t bios_translate_addr(void *opaque, uint64_t srcaddr) return srcaddr + dstaddr; } +static uint64_t get_max_kernel_cmdline_size(void) +{ + uint64_t *size_ptr = rom_ptr(KERN_PARM_AREA_SIZE_ADDR, sizeof(*size_ptr)); + + if (size_ptr) { + uint64_t size; + + size = be64_to_cpu(*size_ptr); + if (size != 0) { + return size; + } + } + return LEGACY_KERN_PARM_AREA_SIZE; +} + static void s390_ipl_realize(DeviceState *dev, Error **errp) { MachineState *ms = MACHINE(qdev_get_machine()); @@ -197,10 +213,11 @@ static void s390_ipl_realize(DeviceState *dev, Error **errp) ipl->start_addr = KERN_IMAGE_START; /* Overwrite parameters in the kernel image, which are "rom" */ if (parm_area) { - if (cmdline_size > KERN_PARM_AREA_SIZE) { + uint64_t max_cmdline_size = get_max_kernel_cmdline_size(); + if (cmdline_size > max_cmdline_size) { error_setg(errp, "kernel command line exceeds maximum size: %zu > %lu", - cmdline_size, KERN_PARM_AREA_SIZE); + cmdline_size, max_cmdline_size); return; }
In the past s390 used a fixed command line length of 896 bytes. This has changed with the Linux commit 5ecb2da660ab ("s390: support command lines longer than 896 bytes"). There is now a parm area indicating the maximum command line size. This parm area has always been initialized to zero, so with older kernels this field would read zero and we must then assume that only 896 bytes are available. Acked-by: Viktor Mihajlovski <mihajlov@de.ibm.com> Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com> --- hw/s390x/ipl.c | 23 ++++++++++++++++++++--- 1 file changed, 20 insertions(+), 3 deletions(-)