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s390/startup: avoid save_area_sync overflow

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Currently we overflow save_area_sync and write over
save_area_async. Although this is not a real problem make
startup_pgm_check_handler consistent with late pgm check handler and
store [%r0,%r7] directly into gpregs_save_area.

Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
This commit is contained in:
Vasily Gorbik 2020-09-24 19:07:04 +02:00
parent 1c7c83e8d2
commit 2835c2ea95
1 changed files with 11 additions and 10 deletions
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21
arch/s390/boot/head.S
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@ -360,22 +360,23 @@ ENTRY(startup_kdump)
# the save area and does disabled wait with a faulty address.
#
ENTRY(startup_pgm_check_handler)
stmg %r0,%r15,__LC_SAVE_AREA_SYNC
la %r1,4095
stctg %c0,%c15,__LC_CREGS_SAVE_AREA-4095(%r1)
mvc __LC_GPREGS_SAVE_AREA-4095(128,%r1),__LC_SAVE_AREA_SYNC
mvc __LC_PSW_SAVE_AREA-4095(16,%r1),__LC_PGM_OLD_PSW
stmg %r8,%r15,__LC_SAVE_AREA_SYNC
la %r8,4095
stctg %c0,%c15,__LC_CREGS_SAVE_AREA-4095(%r8)
stmg %r0,%r7,__LC_GPREGS_SAVE_AREA-4095(%r8)
mvc __LC_GPREGS_SAVE_AREA-4095+64(64,%r8),__LC_SAVE_AREA_SYNC
mvc __LC_PSW_SAVE_AREA-4095(16,%r8),__LC_PGM_OLD_PSW
mvc __LC_RETURN_PSW(16),__LC_PGM_OLD_PSW
ni __LC_RETURN_PSW,0xfc # remove IO and EX bits
ni __LC_RETURN_PSW+1,0xfb # remove MCHK bit
oi __LC_RETURN_PSW+1,0x2 # set wait state bit
larl %r2,.Lold_psw_disabled_wait
stg %r2,__LC_PGM_NEW_PSW+8
l %r15,.Ldump_info_stack-.Lold_psw_disabled_wait(%r2)
larl %r9,.Lold_psw_disabled_wait
stg %r9,__LC_PGM_NEW_PSW+8
l %r15,.Ldump_info_stack-.Lold_psw_disabled_wait(%r9)
brasl %r14,print_pgm_check_info
.Lold_psw_disabled_wait:
la %r1,4095
lmg %r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)
la %r8,4095
lmg %r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r8)
lpswe __LC_RETURN_PSW # disabled wait
.Ldump_info_stack:
.long 0x5000 + PAGE_SIZE - STACK_FRAME_OVERHEAD