The MIPS n32 ABI is basically n64 with the address space (i.e. pointer
width) shrinked to 32 bits. Meanwhile the current code treats it as
o32-like based on TARGET_ABI_BITS, which causes problems with n32
syscalls utilizing 64-bit offsets, like pread64, affecting most (if not
all) recently built n32 binaries.
This partially solves issue #909 ("qemu-mipsn32(el) user mode emulator
fails to execute any recently built n32 binaries"); with this change
applied, the built qemu-mipsn32el is able to progress beyond the
pread64, and finish _dl_start_user for the "getting ld.so load libc.so"
case. The program later dies with SIGBUS, though, due to _dl_start_user
not maintaining stack alignment after removing ld.so itself from argv,
and qemu-user starting to enforce alignment recently, but that is
orthogonal to the issue here; the more common case of chrooting is
working, verified with my own-built Gentoo n32 sysroot. (Depending on
the exact ISA used, one may have to explicitly specify QEMU_CPU, which
is the case for my chroot.)
Buglink: https://gitlab.com/qemu-project/qemu/-/issues/909
Signed-off-by: WANG Xuerui <xe...@gentoo.org>
Cc: Laurent Vivier <laur...@vivier.eu>
Cc: Philippe Mathieu-Daudé <f4...@amsat.org>
Cc: Jiaxun Yang <jiaxun.y...@flygoat.com>
Cc: Andreas K. Hüttel <dilfri...@gentoo.org>
---
P.S. This patch is done with my Gentoo hat on, so I'm not using my
usual xen0n.name address. I'd like to add a mailmap entry for correct
shortlog display though, but it seems there's no category for "merely
preference" mappings yet. What should I do in this case?
linux-user/user-internals.h | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/linux-user/user-internals.h b/linux-user/user-internals.h
index a8fdd6933b2..ee152ccfaa8 100644
--- a/linux-user/user-internals.h
+++ b/linux-user/user-internals.h
@@ -112,7 +112,7 @@ static inline int is_error(abi_long ret)
return (abi_ulong)ret >= (abi_ulong)(-4096);
}
-#if TARGET_ABI_BITS == 32
+#if (TARGET_ABI_BITS == 32) && !defined(TARGET_ABI_MIPSN32)
static inline uint64_t target_offset64(uint32_t word0, uint32_t word1)
{
#ifdef TARGET_WORDS_BIGENDIAN
@@ -121,7 +121,7 @@ static inline uint64_t target_offset64(uint32_t word0,
uint32_t word1)
return ((uint64_t)word1 << 32) | word0;
#endif
}
-#else /* TARGET_ABI_BITS == 32 */
+#else /* TARGET_ABI_BITS == 32 && !defined(TARGET_ABI_MIPSN32) */
static inline uint64_t target_offset64(uint64_t word0, uint64_t word1)
{
return word0;
@@ -136,7 +136,7 @@ static inline int regpairs_aligned(void *cpu_env, int num)
{
return ((((CPUARMState *)cpu_env)->eabi) == 1) ;
}
-#elif defined(TARGET_MIPS) && (TARGET_ABI_BITS == 32)
+#elif defined(TARGET_MIPS) && defined(TARGET_ABI_MIPSO32)
static inline int regpairs_aligned(void *cpu_env, int num) { return 1; }
#elif defined(TARGET_PPC) && !defined(TARGET_PPC64)
/*
--
2.35.1
