File opal-prd-Fix-opal-prd-crash.patch of Package skiboot
From ff576aa8187b47f61f902b6a097693d00c937d4c Mon Sep 17 00:00:00 2001 From: Vasant Hegde <hegdevasant@linux.vnet.ibm.com> Date: Mon, 30 Jul 2018 15:28:46 +0530 Subject: [PATCH] opal-prd: Fix opal-prd crash Patch-mainline: v6.2-rc1 Git-commit: ff576aa8187b47f61f902b6a097693d00c937d4c Presently callback function from HBRT uses r11 to point to target function pointer. r12 is garbage. This works fine when we compile with "-no-pie" option (as we don't use r12 to calculate TOC). As per ABIv2 : "r12 : Function entry address at global entry point" With "-pie" compilation option, we have to set r12 to point to global function entry point. So that we can calculate TOC properly. Crash log without this patch: opal-prd[2864]: unhandled signal 11 at 0000000000029320 nip 00000 00102012830 lr 0000000102016890 code 1 Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com> CC: Jeremy Kerr <jk@ozlabs.org> CC: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Acked-by: Jeremy Kerr <jk@ozlabs.org> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Stewart Smith <stewart@linux.ibm.com> --- external/opal-prd/thunk.S | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/external/opal-prd/thunk.S b/external/opal-prd/thunk.S index e09cef940099..d0ccd6491805 100644 --- a/external/opal-prd/thunk.S +++ b/external/opal-prd/thunk.S @@ -119,7 +119,7 @@ call_le: std %r0,(32+16)(%r1) /* Branch to original function */ - mtlr %r11 + mtlr %r12 blrl /* Restore stack and LR */ @@ -137,7 +137,7 @@ call_le: /* Callback from HBRT. There is one entry point per function. * * We assume the proper r2 is already set via the OPD, so we grab our - * target function pointer in r11 and jump to call_le + * target function pointer in r12 and jump to call_le */ #define CALLBACK_THUNK(name) \ .pushsection ".text","ax" ;\ @@ -146,7 +146,7 @@ name##_thunk: ;\ .long 0x00000038 | le_si16(__NR_switch_endian) ;\ /* byteswapped li %r0,__NR_switch_endian */ ;\ .long 0x02000044 /* byteswapped sc */ ;\ - ld %r11,name@got(%r2) ;\ + ld %r12,name@got(%r2) ;\ b call_le ;\ .popsection ;\ .pushsection ".data.thunk_opd","aw" ;\ -- 2.19.2
