summaryrefslogtreecommitdiffstats
path: root/toolchain/uClibc/patches-0.9.31/901-MIPS-restore-INLINE_SYSCALL-macro.patch
diff options
context:
space:
mode:
Diffstat (limited to 'toolchain/uClibc/patches-0.9.31/901-MIPS-restore-INLINE_SYSCALL-macro.patch')
-rw-r--r--toolchain/uClibc/patches-0.9.31/901-MIPS-restore-INLINE_SYSCALL-macro.patch110
1 files changed, 110 insertions, 0 deletions
diff --git a/toolchain/uClibc/patches-0.9.31/901-MIPS-restore-INLINE_SYSCALL-macro.patch b/toolchain/uClibc/patches-0.9.31/901-MIPS-restore-INLINE_SYSCALL-macro.patch
new file mode 100644
index 000000000..4ba09424b
--- /dev/null
+++ b/toolchain/uClibc/patches-0.9.31/901-MIPS-restore-INLINE_SYSCALL-macro.patch
@@ -0,0 +1,110 @@
+From 911bf867eb82e28799e81578c50d82ee166cebb5 Mon Sep 17 00:00:00 2001
+From: Gabor Juhos <juhosg@openwrt.org>
+Date: Tue, 6 Apr 2010 17:25:56 +0200
+Subject: [PATCH] MIPS: restore INLINE_SYSCALL macro
+
+The MIPS specific INLINE_SYSCALL macro has been renamed to
+INLINE_SYSCALL_NCS with:
+
+ 763bbf9e9a27426c9be8322dca5ddf2cb4dbc464
+
+ syscall: unify part 2: NCS variety
+
+ Declare common NCS (non-constant syscall) variants and convert the
+ existing ports over to this.
+
+This change breaks system calls. The code generated with using of the
+new macro does not obey the restartable syscall convention used by the
+linux kernel. When it tries to restart the syscall the errno value is
+not being replaced by the syscall number.
+
+This causes weird behaviour of the 'ping' command in busybox for
+example:
+
+root@OpenWrt:/# ping 192.168.1.254
+PING 192.168.1.254 (192.168.1.254): 56 data bytes
+64 bytes from 192.168.1.254: seq=0 ttl=128 time=6.292 ms
+ping: recvfrom: Function not implemented
+64 bytes from 192.168.1.254: seq=1 ttl=128 time=0.719 ms
+ping: recvfrom: Function not implemented
+64 bytes from 192.168.1.254: seq=2 ttl=128 time=0.489 ms
+ping: recvfrom: Function not implemented
+64 bytes from 192.168.1.254: seq=3 ttl=128 time=0.486 ms
+ping: recvfrom: Function not implemented
+64 bytes from 192.168.1.254: seq=4 ttl=128 time=0.487 ms
+ping: recvfrom: Function not implemented
+64 bytes from 192.168.1.254: seq=5 ttl=128 time=0.939 ms
+ping: recvfrom: Function not implemented
+64 bytes from 192.168.1.254: seq=6 ttl=128 time=0.971 ms
+ping: recvfrom: Function not implemented
+64 bytes from 192.168.1.254: seq=7 ttl=128 time=0.488 ms
+ping: recvfrom: Funct^C
+--- 192.168.1.254 ping statistics ---
+9 packets transmitted, 9 packets received, 0% packet loss
+round-trip min/avg/max = 0.486/1.307/6.292 ms
+root@OpenWrt:/#
+
+Here is the relevant assembler code parts of the 'recvfrom' function:
+
+with the current INLINE_SYSCALL_NCS:
+00000000 <__GI_recvfrom>:
+ ...
+ 2c: 24021050 li v0,4176
+ 30: 8fd1003c lw s1,60(s8)
+ 34: 8fd00038 lw s0,56(s8)
+ 38: 27bdffe0 addiu sp,sp,-32
+ 3c: afb00010 sw s0,16(sp)
+ 40: afb10014 sw s1,20(sp) <-- wrong
+ 44: 0000000c syscall
+ 48: 27bd0020 addiu sp,sp,32
+ ...
+
+with the old INLINE_SYSCALL:
+00000000 <__libc_recvfrom>:
+ ...
+ 28: 8fd0003c lw s0,60(s8)
+ 2c: 8fc20038 lw v0,56(s8)
+ 30: 27bdffe0 addiu sp,sp,-32
+ 34: afa20010 sw v0,16(sp)
+ 38: afb00014 sw s0,20(sp)
+ 3c: 24021050 li v0,4176 <-- good
+ 40: 0000000c syscall
+ 44: 27bd0020 addiu sp,sp,32
+ ...
+
+Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
+Cc: Mike Frysinger <vapier@gentoo.org>
+---
+Notes:
+
+The ideal solution would to fix the 'internal_syscall' macros to generate
+correct code for the NCS case as well. However the INLINE_SYSCALL macro
+generates smaller code if the syscall number is constant, so it is
+useful in such cases.
+
+Additionally, the current INLINE_SYSCALL_NCS in the 'mips/bits/syscall.h'
+is a duplicate of the one in the 'common/bits/syscalls-common.h' so it
+should be removed anyway.
+---
+ libc/sysdeps/linux/mips/bits/syscalls.h | 4 ++--
+ 1 files changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/libc/sysdeps/linux/mips/bits/syscalls.h b/libc/sysdeps/linux/mips/bits/syscalls.h
+index 28b0f91..944d038 100644
+--- a/libc/sysdeps/linux/mips/bits/syscalls.h
++++ b/libc/sysdeps/linux/mips/bits/syscalls.h
+@@ -19,9 +19,9 @@
+
+ /* Define a macro which expands into the inline wrapper code for a system
+ call. */
+-#define INLINE_SYSCALL_NCS(name, nr, args...) \
++#define INLINE_SYSCALL(name, nr, args...) \
+ ({ INTERNAL_SYSCALL_DECL(err); \
+- long result_var = INTERNAL_SYSCALL_NCS (name, err, nr, args); \
++ long result_var = INTERNAL_SYSCALL(name, err, nr, args); \
+ if ( INTERNAL_SYSCALL_ERROR_P (result_var, err) ) \
+ { \
+ __set_errno (INTERNAL_SYSCALL_ERRNO (result_var, err)); \
+--
+1.5.3.2
+