On 7/27/26 13:56, Laurent Vivier wrote:
Le 27/07/2026 à 13:48, Laurent Vivier a écrit :
On real SH4 hardware, the address space is split between user mode
(U0, 0x00000000-0x7fffffff) and kernel mode (P1-P4, 0x80000000-0xffffffff),
so TARGET_VIRT_ADDR_SPACE_BITS was set to 31 for CONFIG_USER_ONLY.
However, qemu-user does not emulate the MMU, so this limit is not needed.
The only effect is to restrict reserved_va to 2 GB, causing OOM failures
for memory-intensive builds (e.g. webkit2gtk on Debian sh4 buildds).
Set TARGET_VIRT_ADDR_SPACE_BITS to 32 unconditionally, like most other
32-bit targets. Also fix the TASK_UNMAPPED_BASE macro to use 1ull instead
of 1u to avoid undefined behavior when shifting by 32.
Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/4093
Reported-by: John Paul Adrian Glaubitz <[email protected]>
Signed-off-by: Laurent Vivier <[email protected]>
Reviewed-by: Helge Deller <[email protected]>
---
linux-user/sh4/target_mman.h | 2 +-
target/sh4/cpu-param.h | 6 +-----
2 files changed, 2 insertions(+), 6 deletions(-)
diff --git a/linux-user/sh4/target_mman.h b/linux-user/sh4/target_mman.h
index dd9016081e9f..2d05837c2f36 100644
--- a/linux-user/sh4/target_mman.h
+++ b/linux-user/sh4/target_mman.h
@@ -1,6 +1,6 @@
/* arch/sh/include/asm/processor_32.h */
#define TASK_UNMAPPED_BASE \
- TARGET_PAGE_ALIGN((1u << TARGET_VIRT_ADDR_SPACE_BITS) / 3)
+ TARGET_PAGE_ALIGN((1ull << TARGET_VIRT_ADDR_SPACE_BITS) / 3)
/* arch/sh/include/asm/elf.h */
#define ELF_ET_DYN_BASE (TASK_UNMAPPED_BASE * 2)
diff --git a/target/sh4/cpu-param.h b/target/sh4/cpu-param.h
index c3b8114e538b..d95827078260 100644
--- a/target/sh4/cpu-param.h
+++ b/target/sh4/cpu-param.h
@@ -9,10 +9,6 @@
#define SH4_CPU_PARAM_H
#define TARGET_PAGE_BITS 12 /* 4k */
-#ifdef CONFIG_USER_ONLY
-# define TARGET_VIRT_ADDR_SPACE_BITS 31
-#else
-# define TARGET_VIRT_ADDR_SPACE_BITS 32
-#endif
+#define TARGET_VIRT_ADDR_SPACE_BITS 32
#endif
