From fbe765680d1fe9d08187ea4dad5041a7955a2c3a Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Tue, 5 Jun 2012 09:59:52 +0200 Subject: s390/smp: make absolute lowcore / cpu restart parameter accesses more robust Setting the cpu restart parameters is done in three different fashions: - directly setting the four parameters individually - copying the four parameters with memcpy (using 4 * sizeof(long)) - copying the four parameters using a private structure In addition code in entry*.S relies on a certain order of the restart members of struct _lowcore. Make all of this more robust to future changes by adding a mem_absolute_assign(dest, val) define, which assigns val to dest using absolute addressing mode. Also the load multiple instructions in entry*.S have been split into separate load instruction so the order of the struct _lowcore members doesn't matter anymore. In addition move the prototypes of memcpy_real/absolute from uaccess.h to processor.h. These memcpy* variants are not related to uaccess at all. string.h doesn't seem to match as well, so lets use processor.h. Also replace the eight byte array in struct _lowcore which represents a misaliged u64 with a u64. The compiler will always create code that handles the misaligned u64 correctly. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- arch/s390/kernel/ipl.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) (limited to 'arch/s390/kernel/ipl.c') diff --git a/arch/s390/kernel/ipl.c b/arch/s390/kernel/ipl.c index 2f6cfd460cb6..25241cd8ddd8 100644 --- a/arch/s390/kernel/ipl.c +++ b/arch/s390/kernel/ipl.c @@ -1528,15 +1528,12 @@ static struct shutdown_action __refdata dump_action = { static void dump_reipl_run(struct shutdown_trigger *trigger) { - struct { - void *addr; - __u32 csum; - } __packed ipib; - - ipib.csum = csum_partial(reipl_block_actual, - reipl_block_actual->hdr.len, 0); - ipib.addr = reipl_block_actual; - memcpy_absolute(&S390_lowcore.ipib, &ipib, sizeof(ipib)); + unsigned long ipib = (unsigned long) &reipl_block_actual; + unsigned int csum; + + csum = csum_partial(reipl_block_actual, reipl_block_actual->hdr.len, 0); + mem_assign_absolute(S390_lowcore.ipib, ipib); + mem_assign_absolute(S390_lowcore.ipib_checksum, csum); dump_run(trigger); } -- cgit v1.2.3-55-g7522