Re: newest kernel

[Pete Popov <ppopov@mvista.com>]

Jun Sun wrote:

>The patch seems to be just a fast implementation of sysmips().  Why would it
>solve an otherwise illegal instruction problem?
>
>George, what was exactly the error and the faulty instruction?
>
This is the pthread patch, so it's not just fast sysmips.  I think 
George's tar and find are probably linked with pthread, thus causing the 
problem. 

Pete

>Jun
>
>Pete Popov wrote:
>
>>George Gensure wrote:
>>
>>>I build the 2.4.3 #5 kernel from the CVS source, and have had some
>>>trouble with specific programs.  I get illegal instruction errors on
>>>find and tar.  Is there anything I can do to correct this?
>>>
>>I'm guessing you're running into the sys_sysmips problem. A patch has
>>not yet been applied to the oss.sgi.com kernel.  I've attached a patch
>>from Florian that seems to work well and should apply cleanly.
>>
>>Pete
>>
>>  ------------------------------------------------------------------------------
>>diff -Nur linux.orig/arch/mips/kernel/Makefile linux/arch/mips/kernel/Makefile
>>--- linux.orig/arch/mips/kernel/Makefile        Mon Apr  9 00:23:08 2001
>>+++ linux/arch/mips/kernel/Makefile     Mon Apr  9 00:23:34 2001
>>@@ -20,7 +20,7 @@
>> obj-y                          += branch.o process.o signal.o entry.o \
>>                                   traps.o ptrace.o vm86.o ioport.o reset.o \
>>                                   semaphore.o setup.o syscall.o sysmips.o \
>>-                                  ipc.o scall_o32.o unaligned.o
>>+                                  ipc.o scall_o32.o unaligned.o fast-sysmips.o
>> obj-$(CONFIG_MODULES)          += mips_ksyms.o
>>
>> ifdef CONFIG_CPU_R3000
>>@@ -69,5 +69,6 @@
>>
>> entry.o: entry.S
>> head.o: head.S
>>+fast-sysmips.o: fast-sysmips.S
>>
>> include $(TOPDIR)/Rules.make
>>diff -Nur linux.orig/arch/mips/kernel/fast-sysmips.S linux/arch/mips/kernel/fast-sysmips.S
>>--- linux.orig/arch/mips/kernel/fast-sysmips.S  Thu Jan  1 01:00:00 1970
>>+++ linux/arch/mips/kernel/fast-sysmips.S       Mon Apr  9 00:28:20 2001
>>@@ -0,0 +1,85 @@
>>+/*
>>+ * MIPS_ATOMIC_SET asm implementation for ll/sc capable cpus
>>+ *
>>+ * This file is subject to the terms and conditions of the GNU General Public
>>+ * License.  See the file "COPYING" in the main directory of this archive
>>+ * for more details.
>>+ *
>>+ * Copyright (C) 2001 Florian Lohoff <flo@rfc822.org>
>>+ *
>>+ */
>>+#include <asm/asm.h>
>>+#include <asm/mipsregs.h>
>>+#include <asm/regdef.h>
>>+#include <asm/stackframe.h>
>>+#include <asm/isadep.h>
>>+#include <asm/unistd.h>
>>+#include <asm/sysmips.h>
>>+#include <asm/offset.h>
>>+#include <asm/errno.h>
>>+
>>+#define PT_TRACESYS     0x00000002
>>+
>>+       EXPORT(fast_sysmips)
>>+
>>+       .set    noreorder
>>+
>>+       li      t0, MIPS_ATOMIC_SET
>>+       beq     a0, t0, 1f
>>+        nop
>>+       j       sys_sysmips
>>+        nop
>>+
>>+1:
>>+
>>+       # a0 - MIPS_ATOMIC_SET
>>+       # a1 - mem ptr
>>+       # a2 - value
>>+
>>+       addiu   sp, sp, -8                      # Reserve space
>>+       sw      a0, (sp)                        # Save arg0
>>+
>>+       addiu   a0, a1, 4                       # addr+size
>>+       ori     v0, a1, 4                       # addr | size
>>+       lw      v1, THREAD_CURDS(gp)            # current->thread.current_ds
>>+       or      v0, v0, a0                      # addr | size | (addr+size)
>>+       and     v1, v1, v0                      # (mask)&(addr | size | (addr+size)
>>+       bltz    v1, 5f
>>+        nop
>>+
>>+2:
>>+       ll      v0, (a1)
>>+       move    t0, a2
>>+       sc      t0, (a1)
>>+       beqz    t0, 2b
>>+        nop
>>+
>>+       sw      v0, PT_R2+8(sp)                 # Result value
>>+       sw      zero, PT_R7+8(sp)               # Success indicator
>>+
>>+       lw      t0, TASK_PTRACE(gp)             # syscall tracing enabled?
>>+       andi    t0, PT_TRACESYS
>>+       bnez    t0, 3f
>>+        nop
>>+
>>+4:
>>+       lw      a0, (sp)                        # Restore arg0
>>+       addiu   sp, sp, 8                       # Restore sp
>>+
>>+       j       o32_ret_from_sys_call
>>+        nop
>>+
>>+3:
>>+       sw      ra, 4(sp)
>>+       jal     syscall_trace
>>+        nop
>>+       lw      ra, 4(sp)
>>+       j       4b
>>+        nop
>>+
>>+5:
>>+       lw      a0, (sp)                        # Restore arg0
>>+       addiu   sp, sp, 8                       # Restore sp
>>+       j       ra
>>+        li     v0, -EFAULT
>>+
>>diff -Nur linux.orig/arch/mips/kernel/irix5sys.h linux/arch/mips/kernel/irix5sys.h
>>--- linux.orig/arch/mips/kernel/irix5sys.h      Mon Apr  9 00:16:29 2001
>>+++ linux/arch/mips/kernel/irix5sys.h   Sun Apr  8 21:21:16 2001
>>@@ -69,7 +69,7 @@
>> SYS(irix_getgid, 0)                    /* 1047  getgid()              V*/
>> SYS(irix_unimp, 0)                     /* 1048  (XXX IRIX 4 ssig)     V*/
>> SYS(irix_msgsys, 6)                    /* 1049  sys_msgsys            V*/
>>-SYS(sys_sysmips, 4)                    /* 1050  sysmips()            HV*/
>>+SYS(fast_sysmips, 4)                   /* 1050  sysmips()            HV*/
>> SYS(irix_unimp, 0)                     /* 1051  XXX sysacct()        IV*/
>> SYS(irix_shmsys, 5)                    /* 1052  sys_shmsys            V*/
>> SYS(irix_semsys, 0)                    /* 1053  sys_semsys            V*/
>>diff -Nur linux.orig/arch/mips/kernel/syscalls.h linux/arch/mips/kernel/syscalls.h
>>--- linux.orig/arch/mips/kernel/syscalls.h      Mon Apr  9 00:16:30 2001
>>+++ linux/arch/mips/kernel/syscalls.h   Sun Apr  8 21:21:43 2001
>>@@ -163,7 +163,7 @@
>> SYS(sys_writev, 3)
>> SYS(sys_cacheflush, 3)
>> SYS(sys_cachectl, 3)
>>-SYS(sys_sysmips, 4)
>>+SYS(fast_sysmips, 4)
>> SYS(sys_ni_syscall, 0)                         /* 4150 */
>> SYS(sys_getsid, 1)
>> SYS(sys_fdatasync, 0)
>>