| Message ID | 20231031095519.73311-2-frankja@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | s390x: Improve console handling | expand |
On Tue, 31 Oct 2023 09:55:17 +0000 Janosch Frank <frankja@linux.ibm.com> wrote: > The current implementation needs to allocate a page for stsi 1.1.1 and > 3.2.2. As such it's not usable before the allocator is set > up. > > Unfortunately we might end up with detect_host calls before the > allocator setup is done. For example in the SCLP console setup code. > > Let's allocate the stsi storage on the stack to solve that problem. > > Signed-off-by: Janosch Frank <frankja@linux.ibm.com> I like this solution :) Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> > --- > lib/s390x/hardware.c | 11 +++++------ > 1 file changed, 5 insertions(+), 6 deletions(-) > > diff --git a/lib/s390x/hardware.c b/lib/s390x/hardware.c > index 2bcf9c4c..21752562 100644 > --- a/lib/s390x/hardware.c > +++ b/lib/s390x/hardware.c > @@ -13,6 +13,7 @@ > #include <libcflat.h> > #include <alloc_page.h> > #include <asm/arch_def.h> > +#include <asm/page.h> > #include "hardware.h" > #include "stsi.h" > > @@ -21,9 +22,10 @@ static const uint8_t qemu_ebcdic[] = { 0xd8, 0xc5, 0xd4, 0xe4 }; > /* The string "KVM/" in EBCDIC */ > static const uint8_t kvm_ebcdic[] = { 0xd2, 0xe5, 0xd4, 0x61 }; > > -static enum s390_host do_detect_host(void *buf) > +static enum s390_host do_detect_host(void) > { > - struct sysinfo_3_2_2 *stsi_322 = buf; > + uint8_t buf[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE))); > + struct sysinfo_3_2_2 *stsi_322 = (struct sysinfo_3_2_2 *)buf; > > if (stsi_get_fc() == 2) > return HOST_IS_LPAR; > @@ -56,14 +58,11 @@ enum s390_host detect_host(void) > { > static enum s390_host host = HOST_IS_UNKNOWN; > static bool initialized = false; > - void *buf; > > if (initialized) > return host; > > - buf = alloc_page(); > - host = do_detect_host(buf); > - free_page(buf); > + host = do_detect_host(); > initialized = true; > return host; > }
diff --git a/lib/s390x/hardware.c b/lib/s390x/hardware.c index 2bcf9c4c..21752562 100644 --- a/lib/s390x/hardware.c +++ b/lib/s390x/hardware.c @@ -13,6 +13,7 @@ #include <libcflat.h> #include <alloc_page.h> #include <asm/arch_def.h> +#include <asm/page.h> #include "hardware.h" #include "stsi.h" @@ -21,9 +22,10 @@ static const uint8_t qemu_ebcdic[] = { 0xd8, 0xc5, 0xd4, 0xe4 }; /* The string "KVM/" in EBCDIC */ static const uint8_t kvm_ebcdic[] = { 0xd2, 0xe5, 0xd4, 0x61 }; -static enum s390_host do_detect_host(void *buf) +static enum s390_host do_detect_host(void) { - struct sysinfo_3_2_2 *stsi_322 = buf; + uint8_t buf[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE))); + struct sysinfo_3_2_2 *stsi_322 = (struct sysinfo_3_2_2 *)buf; if (stsi_get_fc() == 2) return HOST_IS_LPAR; @@ -56,14 +58,11 @@ enum s390_host detect_host(void) { static enum s390_host host = HOST_IS_UNKNOWN; static bool initialized = false; - void *buf; if (initialized) return host; - buf = alloc_page(); - host = do_detect_host(buf); - free_page(buf); + host = do_detect_host(); initialized = true; return host; }
The current implementation needs to allocate a page for stsi 1.1.1 and 3.2.2. As such it's not usable before the allocator is set up. Unfortunately we might end up with detect_host calls before the allocator setup is done. For example in the SCLP console setup code. Let's allocate the stsi storage on the stack to solve that problem. Signed-off-by: Janosch Frank <frankja@linux.ibm.com> --- lib/s390x/hardware.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-)