On Wed, May 11, 2022 at 02:05:29PM +0200, Heiko Carstens wrote: > llvm's integrated assembler cannot handle immediate values which are > calculated with two local labels: > > arch/s390/purgatory/head.S:139:11: error: invalid operand for instruction > aghi %r8,-(.base_crash-purgatory_start) > > Workaround this by partially rewriting the code. > > Signed-off-by: Heiko Carstens <hca@xxxxxxxxxxxxx> > --- > arch/s390/purgatory/head.S | 29 ++++++++++++++++++++++------- > 1 file changed, 22 insertions(+), 7 deletions(-) ... > - aghi %r10,stack-purgatory_start > + larl %r0,purgatory_start > + slgrk %r0,%r7,%r0 > + agr %r10,%r0 Same problem here: slgrk does not work for MARCH=z10. So new version looks like: >From 99e011fa48d9fe90f6d3d58cf89f738afddf394f Mon Sep 17 00:00:00 2001 From: Heiko Carstens <hca@xxxxxxxxxxxxx> Date: Sat, 7 May 2022 20:08:55 +0200 Subject: [PATCH 4/7] s390/purgatory: workaround llvm's IAS limitations llvm's integrated assembler cannot handle immediate values which are calculated with two local labels: arch/s390/purgatory/head.S:139:11: error: invalid operand for instruction aghi %r8,-(.base_crash-purgatory_start) Workaround this by partially rewriting the code. Signed-off-by: Heiko Carstens <hca@xxxxxxxxxxxxx> --- arch/s390/purgatory/head.S | 30 +++++++++++++++++++++++------- 1 file changed, 23 insertions(+), 7 deletions(-) diff --git a/arch/s390/purgatory/head.S b/arch/s390/purgatory/head.S index 3d1c31e0cf3d..6f835124ee82 100644 --- a/arch/s390/purgatory/head.S +++ b/arch/s390/purgatory/head.S @@ -44,11 +44,14 @@ .endm .macro MEMSWAP dst,src,buf,len -10: cghi \len,bufsz +10: larl %r0,purgatory_end + larl %r1,stack + slgr %r0,%r1 + cgr \len,%r0 jh 11f lgr %r4,\len j 12f -11: lghi %r4,bufsz +11: lgr %r4,%r0 12: MEMCPY \buf,\dst,%r4 MEMCPY \dst,\src,%r4 @@ -135,12 +138,18 @@ ENTRY(purgatory_start) .start_crash_kernel: /* Location of purgatory_start in crash memory */ + larl %r0,.base_crash + larl %r1,purgatory_start + slgr %r0,%r1 lgr %r8,%r13 - aghi %r8,-(.base_crash-purgatory_start) + sgr %r8,%r0 /* Destination for this code i.e. end of memory to be swapped. */ + larl %r0,purgatory_end + larl %r1,purgatory_start + slgr %r0,%r1 lg %r9,crash_size-.base_crash(%r13) - aghi %r9,-(purgatory_end-purgatory_start) + sgr %r9,%r0 /* Destination in crash memory, i.e. same as r9 but in crash memory. */ lg %r10,crash_start-.base_crash(%r13) @@ -149,15 +158,19 @@ ENTRY(purgatory_start) /* Buffer location (in crash memory) and size. As the purgatory is * behind the point of no return it can re-use the stack as buffer. */ - lghi %r11,bufsz + larl %r11,purgatory_end larl %r12,stack + slgr %r11,%r12 MEMCPY %r12,%r9,%r11 /* dst -> (crash) buf */ MEMCPY %r9,%r8,%r11 /* self -> dst */ /* Jump to new location. */ lgr %r7,%r9 - aghi %r7,.jump_to_dst-purgatory_start + larl %r0,.jump_to_dst + larl %r1,purgatory_start + slgr %r0,%r1 + agr %r7,%r0 br %r7 .jump_to_dst: @@ -169,7 +182,10 @@ ENTRY(purgatory_start) /* Load new buffer location after jump */ larl %r7,stack - aghi %r10,stack-purgatory_start + lgr %r0,%r7 + larl %r1,purgatory_start + slgr %r0,%r1 + agr %r10,%r0 MEMCPY %r10,%r7,%r11 /* (new) buf -> (crash) buf */ /* Now the code is set up to run from its designated location. Start -- 2.32.0
