[S390] Use diag308 subcodes 3 and 6 for reboot and dump when possible.

This patch fixes a problem with the following scenario:
 1. Linux booted from DASD "A"
 2. Reboot from DASD "B" using "/sys/firmware/reipl/ccw/device"
 3. Reboot DASD "B"
Without this patch in step 3 on newer s390 systems under LPAR instead of
DASD "B", DASD "A" will be booted. The reason is that in step 2 we use CCW
reipl and in step 3 we use DIAG308 (subcode 3) reipl. DIAG308 does not
notice the CCW reipl and still thinks that it has to reboot DASD "A".
Before applying this fix, ensure to have MCF RJ9967101E or z9 GA3 base driver
installed.

Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

diff --git a/arch/s390/kernel/ipl.c b/arch/s390/kernel/ipl.c
index 14bdde9def40b31e221a4c912dedc9dab713c200..db28cca81fef75ec6c1ffcec76c14218dff80d34 100644 (file)
--- a/arch/s390/kernel/ipl.c
+++ b/arch/s390/kernel/ipl.c
@@ -595,7 +595,9 @@ static int reipl_set_type(enum ipl_type type)
 
        switch(type) {
        case IPL_TYPE_CCW:
-               if (MACHINE_IS_VM)
+               if (diag308_set_works)
+                       reipl_method = REIPL_METHOD_CCW_DIAG;
+               else if (MACHINE_IS_VM)
                        reipl_method = REIPL_METHOD_CCW_VM;
                else
                        reipl_method = REIPL_METHOD_CCW_CIO;
@@ -659,8 +661,6 @@ void reipl_run(struct shutdown_trigger *trigger)
        switch (reipl_method) {
        case REIPL_METHOD_CCW_CIO:
                devid.devno = reipl_block_ccw->ipl_info.ccw.devno;
-               if (ipl_info.type == IPL_TYPE_CCW && devid.devno == ipl_devno)
-                       diag308(DIAG308_IPL, NULL);
                devid.ssid  = 0;
                reipl_ccw_dev(&devid);
                break;
@@ -745,6 +745,7 @@ static int __init reipl_ccw_init(void)
        reipl_block_ccw->hdr.version = IPL_PARM_BLOCK_VERSION;
        reipl_block_ccw->hdr.blk0_len = IPL_PARM_BLK0_CCW_LEN;
        reipl_block_ccw->hdr.pbt = DIAG308_IPL_TYPE_CCW;
+       reipl_block_ccw->hdr.flags = DIAG308_FLAGS_LP_VALID;
        /* check if read scp info worked and set loadparm */
        if (sclp_ipl_info.is_valid)
                memcpy(reipl_block_ccw->ipl_info.ccw.load_param,
@@ -753,8 +754,7 @@ static int __init reipl_ccw_init(void)
                /* read scp info failed: set empty loadparm (EBCDIC blanks) */
                memset(reipl_block_ccw->ipl_info.ccw.load_param, 0x40,
                       LOADPARM_LEN);
-       /* FIXME: check for diag308_set_works when enabling diag ccw reipl */
-       if (!MACHINE_IS_VM)
+       if (!MACHINE_IS_VM && !diag308_set_works)
                sys_reipl_ccw_loadparm_attr.attr.mode = S_IRUGO;
        if (ipl_info.type == IPL_TYPE_CCW)
                reipl_block_ccw->ipl_info.ccw.devno = ipl_devno;
@@ -876,7 +876,9 @@ static int dump_set_type(enum dump_type type)
                return -EINVAL;
        switch (type) {
        case DUMP_TYPE_CCW:
-               if (MACHINE_IS_VM)
+               if (diag308_set_works)
+                       dump_method = DUMP_METHOD_CCW_DIAG;
+               else if (MACHINE_IS_VM)
                        dump_method = DUMP_METHOD_CCW_VM;
                else
                        dump_method = DUMP_METHOD_CCW_CIO;

diff --git a/include/asm-s390/ipl.h b/include/asm-s390/ipl.h
index d0dcc9c5f7c35824fdbc3ee0498c665ba0546553..c1b2e50392bb095dcba90a0b797133eb4583e2c1 100644 (file)
--- a/include/asm-s390/ipl.h
+++ b/include/asm-s390/ipl.h
@@ -143,6 +143,10 @@ enum diag308_opt {
        DIAG308_IPL_OPT_DUMP    = 0x20,
 };
 
+enum diag308_flags {
+       DIAG308_FLAGS_LP_VALID  = 0x80,
+};
+
 enum diag308_rc {
        DIAG308_RC_OK   = 1,
 };