Commit e9b9a047 authored by Heiko Carstens's avatar Heiko Carstens Committed by Linus Torvalds

[PATCH] s390: memory detection > 32GB

The kernel takes a very long time to boot if the memory size is bigger then
32767 MB.  The memory size is contained in a structure created by an sclp
call.  The kernel accesses the field with a LH instrution which performs a
sign extension of a 16 bit word.  In the case of a memory size with bit 2^15
set this results in a very large value and the memory detection just loops for
a long time.  In addition if more then 64 GB are used on a 64 bit system the
memory size is read from an incorrect storage location.

Use zero-extention to read the 16 bit memory size and the correct offset to
read the 4 byte memory size on 64 bit.
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 447570cf
......@@ -517,10 +517,10 @@ startup:basr %r13,0 # get base
l %r2, .Lrcp2-.LPG1(%r13) # try with Read SCP
b .Lservicecall-.LPG1(%r13)
.Lprocsccb:
lh %r1,.Lscpincr1-PARMAREA(%r4) # use this one if != 0
chi %r1,0x00
jne .Lscnd
l %r1,.Lscpincr2-PARMAREA(%r4) # otherwise use this one
lhi %r1,0
icm %r1,3,.Lscpincr1-PARMAREA(%r4) # use this one if != 0
jnz .Lscnd
l %r1,.Lscpincr2-PARMAREA+4(%r4) # otherwise use this one
.Lscnd:
xr %r3,%r3 # same logic
ic %r3,.Lscpa1-PARMAREA(%r4)
......
......@@ -518,9 +518,9 @@ startup:basr %r13,0 # get base
l %r2,.Lrcp2-.LPG1(%r13) # try with Read SCP
b .Lservicecall-.LPG1(%r13)
.Lprocsccb:
lh %r1,.Lscpincr1-PARMAREA(%r4) # use this one if != 0
chi %r1,0x00
jne .Lscnd
lghi %r1,0
icm %r1,3,.Lscpincr1-PARMAREA(%r4) # use this one if != 0
jnz .Lscnd
lg %r1,.Lscpincr2-PARMAREA(%r4) # otherwise use this one
.Lscnd:
xr %r3,%r3 # same logic
......
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