[lkml]   [2020]   [May]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[PATCH] openrisc: Fix issue with argument clobbering for clone/fork
Working on the OpenRISC glibc port I found that sometimes clone was
working strange. That the tls data argument sent in r7 was always
wrong. Further investigation revealed that the arguments were getting
clobbered in the entry code. This patch removes the code that writes to
the argument registers. This was likely due to some old code hanging

This patch fixes this up for clone and fork. This fork clobber is
harmless but also useless so remove.

Signed-off-by: Stafford Horne <>
arch/openrisc/kernel/entry.S | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/openrisc/kernel/entry.S b/arch/openrisc/kernel/entry.S
index e4a78571f883..c6481cfc5220 100644
--- a/arch/openrisc/kernel/entry.S
+++ b/arch/openrisc/kernel/entry.S
@@ -1166,13 +1166,13 @@ ENTRY(__sys_clone)
l.movhi r29,hi(sys_clone)
l.ori r29,r29,lo(sys_clone)
l.j _fork_save_extra_regs_and_call
- l.addi r7,r1,0
+ l.nop

l.movhi r29,hi(sys_fork)
l.ori r29,r29,lo(sys_fork)
l.j _fork_save_extra_regs_and_call
- l.addi r3,r1,0
+ l.nop

l.jal _sys_rt_sigreturn
 \ /
  Last update: 2020-05-31 23:26    [W:0.029 / U:6.360 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site