From: Heiko Carstens <heiko.carstens@de.ibm.com> Date: Wed, 22 Jun 2005 00:16:30 +0000 (-0700) Subject: [PATCH] s390: memory detection > 32GB X-Git-Tag: v2.6.13-rc4~130^2~202^2~65 X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=e9b9a04796eade5241452a913ec6f3433437b4f5;p=linux-2.6-omap-h63xx.git [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: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org> --- diff --git a/arch/s390/kernel/head.S b/arch/s390/kernel/head.S index b804c55bd91..658e8de74f8 100644 --- a/arch/s390/kernel/head.S +++ b/arch/s390/kernel/head.S @@ -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) diff --git a/arch/s390/kernel/head64.S b/arch/s390/kernel/head64.S index 8366793bc37..8e2caf9dc18 100644 --- a/arch/s390/kernel/head64.S +++ b/arch/s390/kernel/head64.S @@ -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