On RISC-V, large code model is only compatible with position-depedent
code. However, the configure script checks availability of
-mcmodel=large before determining whether PIC/PIE is enabled, and
disable them.
This is problematic with toolchains that enable PIE by default, where
check for -mcmodel=large will always fail with,
cc1: sorry, unimplemented: code model 'large' with '-fPIC'
and -mcmodel=medany will be silently used instead, causing relocation
failures at runtime with some memory layouts since -mcmodel=medany
requires all data and code to stay within a contiguous 4GiB range.
Let's defer the check for -mcmodel=large until PIC/PIE is ensured
disabled.
Fixes: f1957dc8a334 ("RISC-V: Add to build system")
Reported-by: Han Gao <[email protected]>
Signed-off-by: Yao Zi <[email protected]>
---
configure.ac | 30 +++++++++++++++---------------
1 file changed, 15 insertions(+), 15 deletions(-)
This problem is known to be discovered independently by developers from
Ubuntu and Sophgo, too. However I don't have their accurate information,
so only Han Gao is listed in Reported-by tag.
diff --git a/configure.ac b/configure.ac
index a282bf7bfbc7..a833c7612734 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1543,21 +1543,6 @@ AC_SUBST(TARGET_LDFLAGS_OLDMAGIC)
LDFLAGS="$TARGET_LDFLAGS"
-if test "$target_cpu" = x86_64 || test "$target_cpu" = sparc64 || test
"$target_cpu" = riscv64 ; then
- # Use large model to support 4G memory
- AC_CACHE_CHECK([whether option -mcmodel=large works], grub_cv_cc_mcmodel, [
- CFLAGS="$TARGET_CFLAGS -mcmodel=large"
- AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], [[]])],
- [grub_cv_cc_mcmodel=yes],
- [grub_cv_cc_mcmodel=no])
- ])
- if test "x$grub_cv_cc_mcmodel" = xyes; then
- TARGET_CFLAGS="$TARGET_CFLAGS -mcmodel=large"
- elif test "$target_cpu" = sparc64 || test "$target_cpu" = riscv64; then
- TARGET_CFLAGS="$TARGET_CFLAGS -mcmodel=medany"
- fi
-fi
-
if test "$target_cpu"-"$platform" = x86_64-efi; then
# EFI writes to stack below %rsp, we must not use the red zone
AC_CACHE_CHECK([whether option -mno-red-zone works], grub_cv_cc_no_red_zone,
[
@@ -1666,6 +1651,21 @@ fi]
CFLAGS="$TARGET_CFLAGS"
+if test "$target_cpu" = x86_64 || test "$target_cpu" = sparc64 || test
"$target_cpu" = riscv64 ; then
+ # Use large model to support 4G memory
+ AC_CACHE_CHECK([whether option -mcmodel=large works], grub_cv_cc_mcmodel, [
+ CFLAGS="$TARGET_CFLAGS -mcmodel=large"
+ AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], [[]])],
+ [grub_cv_cc_mcmodel=yes],
+ [grub_cv_cc_mcmodel=no])
+ ])
+ if test "x$grub_cv_cc_mcmodel" = xyes; then
+ TARGET_CFLAGS="$TARGET_CFLAGS -mcmodel=large"
+ elif test "$target_cpu" = sparc64 || test "$target_cpu" = riscv64; then
+ TARGET_CFLAGS="$TARGET_CFLAGS -mcmodel=medany"
+ fi
+fi
+
# Stack smashing protector.
grub_CHECK_STACK_PROTECTOR
AC_ARG_ENABLE([stack-protector],
--
2.51.2
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