linux-user: Tidy and enforce reserved_va initialization
We had a check using TARGET_VIRT_ADDR_SPACE_BITS to make sure that the allocation coming in from the command-line option was not too large, but that didn't include target-specific knowledge about other restrictions on user-space. Remove several target-specific hacks in linux-user/main.c. For MIPS and Nios, we can replace them with proper adjustments to the respective target's TARGET_VIRT_ADDR_SPACE_BITS definition. For ARM, we had no existing ifdef but I suspect that the current default value of 0xf7000000 was chosen with this in mind. Define a workable value in linux-user/arm/, and also document why the special case is required. Signed-off-by: Richard Henderson <rth@twiddle.net> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Message-Id: <20170708025030.15845-3-rth@twiddle.net> Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
This commit is contained in:
parent
de258eb07d
commit
18e80c55bb
|
@ -19,6 +19,10 @@
|
|||
#ifndef ARM_TARGET_CPU_H
|
||||
#define ARM_TARGET_CPU_H
|
||||
|
||||
/* We need to be able to map the commpage.
|
||||
See validate_guest_space in linux-user/elfload.c. */
|
||||
#define MAX_RESERVED_VA 0xffff0000ul
|
||||
|
||||
static inline void cpu_clone_regs(CPUARMState *env, target_ulong newsp)
|
||||
{
|
||||
if (newsp) {
|
||||
|
|
|
@ -60,24 +60,39 @@ do { \
|
|||
} \
|
||||
} while (0)
|
||||
|
||||
#if (TARGET_LONG_BITS == 32) && (HOST_LONG_BITS == 64)
|
||||
/*
|
||||
* When running 32-on-64 we should make sure we can fit all of the possible
|
||||
* guest address space into a contiguous chunk of virtual host memory.
|
||||
*
|
||||
* This way we will never overlap with our own libraries or binaries or stack
|
||||
* or anything else that QEMU maps.
|
||||
*
|
||||
* Many cpus reserve the high bit (or more than one for some 64-bit cpus)
|
||||
* of the address for the kernel. Some cpus rely on this and user space
|
||||
* uses the high bit(s) for pointer tagging and the like. For them, we
|
||||
* must preserve the expected address space.
|
||||
*/
|
||||
# if defined(TARGET_MIPS) || defined(TARGET_NIOS2)
|
||||
/*
|
||||
* MIPS only supports 31 bits of virtual address space for user space.
|
||||
* Nios2 also only supports 31 bits.
|
||||
*/
|
||||
unsigned long reserved_va = 0x77000000;
|
||||
#ifndef MAX_RESERVED_VA
|
||||
# if HOST_LONG_BITS > TARGET_VIRT_ADDR_SPACE_BITS
|
||||
# if TARGET_VIRT_ADDR_SPACE_BITS == 32 && \
|
||||
(TARGET_LONG_BITS == 32 || defined(TARGET_ABI32))
|
||||
/* There are a number of places where we assign reserved_va to a variable
|
||||
of type abi_ulong and expect it to fit. Avoid the last page. */
|
||||
# define MAX_RESERVED_VA (0xfffffffful & TARGET_PAGE_MASK)
|
||||
# else
|
||||
unsigned long reserved_va = 0xf7000000;
|
||||
# define MAX_RESERVED_VA (1ul << TARGET_VIRT_ADDR_SPACE_BITS)
|
||||
# endif
|
||||
# else
|
||||
# define MAX_RESERVED_VA 0
|
||||
# endif
|
||||
#endif
|
||||
|
||||
/* That said, reserving *too* much vm space via mmap can run into problems
|
||||
with rlimits, oom due to page table creation, etc. We will still try it,
|
||||
if directed by the command-line option, but not by default. */
|
||||
#if HOST_LONG_BITS == 64 && TARGET_VIRT_ADDR_SPACE_BITS <= 32
|
||||
unsigned long reserved_va = MAX_RESERVED_VA;
|
||||
#else
|
||||
unsigned long reserved_va;
|
||||
#endif
|
||||
|
||||
|
@ -3978,11 +3993,8 @@ static void handle_arg_reserved_va(const char *arg)
|
|||
unsigned long unshifted = reserved_va;
|
||||
p++;
|
||||
reserved_va <<= shift;
|
||||
if (((reserved_va >> shift) != unshifted)
|
||||
#if HOST_LONG_BITS > TARGET_VIRT_ADDR_SPACE_BITS
|
||||
|| (reserved_va > (1ul << TARGET_VIRT_ADDR_SPACE_BITS))
|
||||
#endif
|
||||
) {
|
||||
if (reserved_va >> shift != unshifted
|
||||
|| (MAX_RESERVED_VA && reserved_va > MAX_RESERVED_VA)) {
|
||||
fprintf(stderr, "Reserved virtual address too big\n");
|
||||
exit(EXIT_FAILURE);
|
||||
}
|
||||
|
|
|
@ -15,8 +15,12 @@
|
|||
#else
|
||||
#define TARGET_LONG_BITS 32
|
||||
#define TARGET_PHYS_ADDR_SPACE_BITS 40
|
||||
# ifdef CONFIG_USER_ONLY
|
||||
# define TARGET_VIRT_ADDR_SPACE_BITS 31
|
||||
# else
|
||||
# define TARGET_VIRT_ADDR_SPACE_BITS 32
|
||||
#endif
|
||||
#endif
|
||||
|
||||
/* Masks used to mark instructions to indicate which ISA level they
|
||||
were introduced in. */
|
||||
|
|
|
@ -226,7 +226,11 @@ qemu_irq *nios2_cpu_pic_init(Nios2CPU *cpu);
|
|||
void nios2_check_interrupts(CPUNios2State *env);
|
||||
|
||||
#define TARGET_PHYS_ADDR_SPACE_BITS 32
|
||||
#ifdef CONFIG_USER_ONLY
|
||||
# define TARGET_VIRT_ADDR_SPACE_BITS 31
|
||||
#else
|
||||
# define TARGET_VIRT_ADDR_SPACE_BITS 32
|
||||
#endif
|
||||
|
||||
#define cpu_init(cpu_model) cpu_generic_init(TYPE_NIOS2_CPU, cpu_model)
|
||||
|
||||
|
|
Loading…
Reference in a new issue