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authorHeiko Carstens <heiko.carstens@de.ibm.com>2007-03-05 23:35:45 +0100
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2007-03-05 23:35:45 +0100
commit9c9c17613a78545a4a93b1370924f62eb282c903 (patch)
treec5b001a52bdf365f386c22c9647a4be05505e9b5 /arch
parentc5dd8586707800cd7bbdefcd675ad7d3c9afcd57 (diff)
[S390] nss: disable kexec.
nss and kexec don't work together since kexec wants to write to the read-only text section of the shared kernel image. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch')
-rw-r--r--arch/s390/Kconfig2
-rw-r--r--arch/s390/kernel/machine_kexec.c5
2 files changed, 7 insertions, 0 deletions
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index d9425f59be9..0f293aa7b0f 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -376,6 +376,8 @@ config SHARED_KERNEL
Select this option, if you want to share the text segment of the
Linux kernel between different VM guests. This reduces memory
usage with lots of guests but greatly increases kernel size.
+ Also if a kernel was IPL'ed from a shared segment the kexec system
+ call will not work.
You should only select this option if you know what you are
doing and want to exploit this feature.
diff --git a/arch/s390/kernel/machine_kexec.c b/arch/s390/kernel/machine_kexec.c
index 52f57af252b..3c77dd36994 100644
--- a/arch/s390/kernel/machine_kexec.c
+++ b/arch/s390/kernel/machine_kexec.c
@@ -19,6 +19,7 @@
#include <asm/system.h>
#include <asm/smp.h>
#include <asm/reset.h>
+#include <asm/ipl.h>
typedef void (*relocate_kernel_t)(kimage_entry_t *, unsigned long);
@@ -29,6 +30,10 @@ int machine_kexec_prepare(struct kimage *image)
{
void *reboot_code_buffer;
+ /* Can't replace kernel image since it is read-only. */
+ if (ipl_flags & IPL_NSS_VALID)
+ return -ENOSYS;
+
/* We don't support anything but the default image type for now. */
if (image->type != KEXEC_TYPE_DEFAULT)
return -EINVAL;