linux-user: Pass image_range to probe_guest_base
Pass a PGBRange structure instead of separate guest_loaddr and guest_hiaddr parameters. This allows NULL to indicate that the image is relocatable, so that image_range->lo == 0 is a valid fixed setting. Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/1890 Tested-by: Helge Deller <deller@gmx.de> Reviewed-by: Warner Losh <imp@bsdimp.com> Reviewed-by: Helge Deller <deller@gmx.de> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Richard Henderson committed
May 29, 2026 at 15:41 UTC
3452cbd09f0db786ea8d9dd9a42648d32e79147b
3 files changed
+27
-34
linux-user/elfload.c
+21
-25
@@ -847,14 +847,13 @@ static bool pgb_try_mmap_set(const PGBAddrs *ga, uintptr_t base, uintptr_t brk)
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/**
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* pgb_addr_set:
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* @ga: output set of guest addrs
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- * @guest_loaddr: guest image low address
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- * @guest_hiaddr: guest image high address
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+ * @image_range: fixed guest image addresses
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* @identity: create for identity mapping
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*
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* Fill in @ga with the image, COMMPAGE and NULL page.
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*/
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-static bool pgb_addr_set(PGBAddrs *ga, abi_ulong guest_loaddr,
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- abi_ulong guest_hiaddr, bool try_identity)
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+static bool pgb_addr_set(PGBAddrs *ga, const PGBRange *image_range,
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+ bool try_identity)
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{
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int n;
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@@ -866,7 +865,7 @@ static bool pgb_addr_set(PGBAddrs *ga, abi_ulong guest_loaddr,
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if (LO_COMMPAGE != -1 && LO_COMMPAGE < mmap_min_addr) {
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return false;
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}
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- if (guest_loaddr != 0 && guest_loaddr < mmap_min_addr) {
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+ if (image_range && image_range->lo < mmap_min_addr) {
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return false;
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}
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}
@@ -892,10 +891,8 @@ static bool pgb_addr_set(PGBAddrs *ga, abi_ulong guest_loaddr,
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}
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/* Add the guest image for ET_EXEC. */
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- if (guest_loaddr) {
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- ga->bounds[n].lo = guest_loaddr;
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- ga->bounds[n].hi = guest_hiaddr;
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- n++;
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+ if (image_range) {
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+ ga->bounds[n++] = *image_range;
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}
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}
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@@ -928,8 +925,8 @@ static void pgb_fail_in_use(const char *image_name)
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exit(EXIT_FAILURE);
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}
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-static void pgb_fixed(const char *image_name, uintptr_t guest_loaddr,
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- uintptr_t guest_hiaddr, uintptr_t align)
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+static void pgb_fixed(const char *image_name, const PGBRange *image_range,
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+ uintptr_t align)
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{
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PGBAddrs ga;
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uintptr_t brk = (uintptr_t)sbrk(0);
@@ -941,7 +938,7 @@ static void pgb_fixed(const char *image_name, uintptr_t guest_loaddr,
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exit(EXIT_FAILURE);
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}
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- if (!pgb_addr_set(&ga, guest_loaddr, guest_hiaddr, !guest_base)
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+ if (!pgb_addr_set(&ga, image_range, !guest_base)
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|| !pgb_try_mmap_set(&ga, guest_base, brk)) {
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pgb_fail_in_use(image_name);
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}
@@ -1026,15 +1023,15 @@ static uintptr_t pgb_find_itree(const PGBAddrs *ga, IntervalTreeRoot *root,
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return pgb_try_mmap_set(ga, base, brk) ? base : -1;
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}
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1029
-static void pgb_dynamic(const char *image_name, uintptr_t guest_loaddr,
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- uintptr_t guest_hiaddr, uintptr_t align)
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+static void pgb_dynamic(const char *image_name, const PGBRange *image_range,
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+ uintptr_t align)
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{
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IntervalTreeRoot *root;
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uintptr_t brk, ret;
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PGBAddrs ga;
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/* Try the identity map first. */
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- if (pgb_addr_set(&ga, guest_loaddr, guest_hiaddr, true)) {
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+ if (pgb_addr_set(&ga, image_range, true)) {
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brk = (uintptr_t)sbrk(0);
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if (pgb_try_mmap_set(&ga, 0, brk)) {
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guest_base = 0;
@@ -1046,7 +1043,7 @@ static void pgb_dynamic(const char *image_name, uintptr_t guest_loaddr,
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* Rebuild the address set for non-identity map.
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* This differs in the mapping of the guest NULL page.
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*/
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- pgb_addr_set(&ga, guest_loaddr, guest_hiaddr, false);
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+ pgb_addr_set(&ga, image_range, false);
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root = read_self_maps();
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@@ -1085,24 +1082,23 @@ static void pgb_dynamic(const char *image_name, uintptr_t guest_loaddr,
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guest_base = ret;
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}
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-void probe_guest_base(const char *image_name, abi_ulong guest_loaddr,
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- abi_ulong guest_hiaddr)
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+void probe_guest_base(const char *image_name, const PGBRange *image_range)
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{
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/* In order to use host shmat, we must be able to honor SHMLBA. */
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uintptr_t align = MAX(SHMLBA, TARGET_PAGE_SIZE);
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/* Sanity check the guest binary. */
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- if (reserved_va && guest_hiaddr > reserved_va) {
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+ if (reserved_va && image_range && image_range->hi > reserved_va) {
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error_report("%s: requires more than reserved virtual "
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- "address space (0x%" PRIx64 " > 0x%lx)",
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- image_name, (uint64_t)guest_hiaddr, reserved_va);
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+ "address space (0x%" VADDR_PRIx " > 0x%lx)",
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+ image_name, image_range->hi, reserved_va);
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exit(EXIT_FAILURE);
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}
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if (have_guest_base) {
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- pgb_fixed(image_name, guest_loaddr, guest_hiaddr, align);
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+ pgb_fixed(image_name, image_range, align);
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} else {
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- pgb_dynamic(image_name, guest_loaddr, guest_hiaddr, align);
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+ pgb_dynamic(image_name, image_range, align);
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}
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/* Reserve and initialize the commpage. */
@@ -1362,10 +1358,10 @@ static void load_elf_image(const char *image_name, const ImageSource *src,
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* Make sure that the low address does not conflict with
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* MMAP_MIN_ADDR or the QEMU application itself.
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*/
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- probe_guest_base(image_name, range.lo, range.hi);
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+ probe_guest_base(image_name, &range);
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} else {
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/* The binary is dynamic; we still need to select guest_base. */
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- probe_guest_base(image_name, 0, 0);
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+ probe_guest_base(image_name, NULL);
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/*
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* Avoid collision with the loader by providing a different
linux-user/flatload.c
+1
-1
@@ -261,7 +261,7 @@ static int load_flat_file(struct linux_binprm * bprm,
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/*
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* Allocate the address space.
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*/
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- probe_guest_base(bprm->filename, 0, 0);
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+ probe_guest_base(bprm->filename, NULL);
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/*
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* there are a couple of cases here, the separate code/data
linux-user/user-internals.h
+5
-8
@@ -83,24 +83,21 @@ typedef struct PGBRange {
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/**
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* probe_guest_base:
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* @image_name: the executable being loaded
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- * @loaddr: the lowest fixed address within the executable
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- * @hiaddr: the highest fixed address within the executable
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+ * @image_range: the fixed addresses within the executable
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*
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* Creates the initial guest address space in the host memory space.
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*
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- * If @loaddr == 0, then no address in the executable is fixed, i.e.
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- * it is fully relocatable. In that case @hiaddr is the size of the
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- * executable minus one.
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+ * If @image_range is NULL, then no address in the executable is fixed,
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+ * i.e. it is fully relocatable.
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*
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* This function will not return if a valid value for guest_base
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* cannot be chosen. On return, the executable loader can expect
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*
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- * target_mmap(loaddr, hiaddr - loaddr + 1, ...)
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+ * target_mmap(i->lo, i->hi - i->lo + 1, ...)
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*
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* to succeed.
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*/
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-void probe_guest_base(const char *image_name,
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- abi_ulong loaddr, abi_ulong hiaddr);
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+void probe_guest_base(const char *image_name, const PGBRange *image_range);
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/* syscall.c */
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int host_to_target_waitstatus(int status);