mirror of https://github.com/xemu-project/xemu.git
linux-user/hppa: Allocate page zero as a commpage
We're about to start validating PAGE_EXEC, which means that we've got to mark page zero executable. We had been special casing this entirely within translate. Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
parent
fbd3c4cff6
commit
eee816c0b9
|
@ -1646,6 +1646,34 @@ static inline void init_thread(struct target_pt_regs *regs,
|
||||||
regs->gr[31] = infop->entry;
|
regs->gr[31] = infop->entry;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
#define LO_COMMPAGE 0
|
||||||
|
|
||||||
|
static bool init_guest_commpage(void)
|
||||||
|
{
|
||||||
|
void *want = g2h_untagged(LO_COMMPAGE);
|
||||||
|
void *addr = mmap(want, qemu_host_page_size, PROT_NONE,
|
||||||
|
MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
|
||||||
|
|
||||||
|
if (addr == MAP_FAILED) {
|
||||||
|
perror("Allocating guest commpage");
|
||||||
|
exit(EXIT_FAILURE);
|
||||||
|
}
|
||||||
|
if (addr != want) {
|
||||||
|
return false;
|
||||||
|
}
|
||||||
|
|
||||||
|
/*
|
||||||
|
* On Linux, page zero is normally marked execute only + gateway.
|
||||||
|
* Normal read or write is supposed to fail (thus PROT_NONE above),
|
||||||
|
* but specific offsets have kernel code mapped to raise permissions
|
||||||
|
* and implement syscalls. Here, simply mark the page executable.
|
||||||
|
* Special case the entry points during translation (see do_page_zero).
|
||||||
|
*/
|
||||||
|
page_set_flags(LO_COMMPAGE, LO_COMMPAGE + TARGET_PAGE_SIZE,
|
||||||
|
PAGE_EXEC | PAGE_VALID);
|
||||||
|
return true;
|
||||||
|
}
|
||||||
|
|
||||||
#endif /* TARGET_HPPA */
|
#endif /* TARGET_HPPA */
|
||||||
|
|
||||||
#ifdef TARGET_XTENSA
|
#ifdef TARGET_XTENSA
|
||||||
|
@ -2326,12 +2354,12 @@ static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
|
||||||
}
|
}
|
||||||
|
|
||||||
#if defined(HI_COMMPAGE)
|
#if defined(HI_COMMPAGE)
|
||||||
#define LO_COMMPAGE 0
|
#define LO_COMMPAGE -1
|
||||||
#elif defined(LO_COMMPAGE)
|
#elif defined(LO_COMMPAGE)
|
||||||
#define HI_COMMPAGE 0
|
#define HI_COMMPAGE 0
|
||||||
#else
|
#else
|
||||||
#define HI_COMMPAGE 0
|
#define HI_COMMPAGE 0
|
||||||
#define LO_COMMPAGE 0
|
#define LO_COMMPAGE -1
|
||||||
#define init_guest_commpage() true
|
#define init_guest_commpage() true
|
||||||
#endif
|
#endif
|
||||||
|
|
||||||
|
@ -2555,7 +2583,7 @@ static void pgb_static(const char *image_name, abi_ulong orig_loaddr,
|
||||||
} else {
|
} else {
|
||||||
offset = -(HI_COMMPAGE & -align);
|
offset = -(HI_COMMPAGE & -align);
|
||||||
}
|
}
|
||||||
} else if (LO_COMMPAGE != 0) {
|
} else if (LO_COMMPAGE != -1) {
|
||||||
loaddr = MIN(loaddr, LO_COMMPAGE & -align);
|
loaddr = MIN(loaddr, LO_COMMPAGE & -align);
|
||||||
}
|
}
|
||||||
|
|
||||||
|
|
Loading…
Reference in New Issue