#include "symtab.h"
#include "tramp-frame.h"
#include "trad-frame.h"
+#include "target.h"
#include "target/target.h"
#include "expop.h"
#include "arch/aarch64-mte-linux.h"
+#include "arch-utils.h"
+#include "value.h"
+
+#include "gdbsupport/selftest.h"
+
/* Signal frame handling.
+------------+ ^
AARCH64_LINUX_SIZEOF_PAUTH, &aarch64_linux_pauth_regset,
"pauth registers", cb_data);
}
+
+ /* Handle MTE registers. */
+ if (tdep->has_mte ())
+ {
+ /* Create this on the fly in order to handle the variable location. */
+ const struct regcache_map_entry mte_regmap[] =
+ {
+ { 1, tdep->mte_reg_base, 4},
+ { 0 }
+ };
+
+ const struct regset aarch64_linux_mte_regset =
+ {
+ mte_regmap, regcache_supply_regset, regcache_collect_regset
+ };
+
+ cb (".reg-aarch-mte", AARCH64_LINUX_SIZEOF_MTE_REGSET,
+ AARCH64_LINUX_SIZEOF_MTE_REGSET, &aarch64_linux_mte_regset,
+ "MTE registers", cb_data);
+ }
}
/* Implement the "core_read_description" gdbarch method. */
struct target_ops *target, bfd *abfd)
{
CORE_ADDR hwcap = linux_get_hwcap (target);
+ CORE_ADDR hwcap2 = linux_get_hwcap2 (target);
+ bool pauth_p = hwcap & AARCH64_HWCAP_PACA;
+ bool mte_p = hwcap2 & HWCAP2_MTE;
return aarch64_read_description (aarch64_linux_core_read_vq (gdbarch, abfd),
- hwcap & AARCH64_HWCAP_PACA);
+ pauth_p, mte_p);
}
/* Implementation of `gdbarch_stap_is_single_operand', as defined in
return {};
}
+/* Helper to get the allocation tag from a 64-bit ADDRESS.
+
+ Return the allocation tag if successful and nullopt otherwise. */
+
+static gdb::optional<CORE_ADDR>
+aarch64_mte_get_atag (CORE_ADDR address)
+{
+ gdb::byte_vector tags;
+
+ /* Attempt to fetch the allocation tag. */
+ if (!target_fetch_memtags (address, 1, tags,
+ static_cast<int> (memtag_type::allocation)))
+ return {};
+
+ /* Only one tag should've been returned. Make sure we got exactly that. */
+ if (tags.size () != 1)
+ error (_("Target returned an unexpected number of tags."));
+
+ /* Although our tags are 4 bits in size, they are stored in a
+ byte. */
+ return tags[0];
+}
+
+/* Implement the tagged_address_p gdbarch method. */
+
+static bool
+aarch64_linux_tagged_address_p (struct gdbarch *gdbarch, struct value *address)
+{
+ gdb_assert (address != nullptr);
+
+ CORE_ADDR addr = value_as_address (address);
+
+ /* Remove the top byte for the memory range check. */
+ addr = address_significant (gdbarch, addr);
+
+ /* Check if the page that contains ADDRESS is mapped with PROT_MTE. */
+ if (!linux_address_in_memtag_page (addr))
+ return false;
+
+ /* We have a valid tag in the top byte of the 64-bit address. */
+ return true;
+}
+
+/* Implement the memtag_matches_p gdbarch method. */
+
+static bool
+aarch64_linux_memtag_matches_p (struct gdbarch *gdbarch,
+ struct value *address)
+{
+ gdb_assert (address != nullptr);
+
+ /* Make sure we are dealing with a tagged address to begin with. */
+ if (!aarch64_linux_tagged_address_p (gdbarch, address))
+ return true;
+
+ CORE_ADDR addr = value_as_address (address);
+
+ /* Fetch the allocation tag for ADDRESS. */
+ gdb::optional<CORE_ADDR> atag = aarch64_mte_get_atag (addr);
+
+ if (!atag.has_value ())
+ return true;
+
+ /* Fetch the logical tag for ADDRESS. */
+ gdb_byte ltag = aarch64_mte_get_ltag (addr);
+
+ /* Are the tags the same? */
+ return ltag == *atag;
+}
+
+/* Implement the set_memtags gdbarch method. */
+
+static bool
+aarch64_linux_set_memtags (struct gdbarch *gdbarch, struct value *address,
+ size_t length, const gdb::byte_vector &tags,
+ memtag_type tag_type)
+{
+ gdb_assert (!tags.empty ());
+ gdb_assert (address != nullptr);
+
+ CORE_ADDR addr = value_as_address (address);
+
+ /* Set the logical tag or the allocation tag. */
+ if (tag_type == memtag_type::logical)
+ {
+ /* When setting logical tags, we don't care about the length, since
+ we are only setting a single logical tag. */
+ addr = aarch64_mte_set_ltag (addr, tags[0]);
+
+ /* Update the value's content with the tag. */
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ gdb_byte *srcbuf = value_contents_raw (address);
+ store_unsigned_integer (srcbuf, sizeof (addr), byte_order, addr);
+ }
+ else
+ {
+ /* Make sure we are dealing with a tagged address to begin with. */
+ if (!aarch64_linux_tagged_address_p (gdbarch, address))
+ return false;
+
+ /* With G being the number of tag granules and N the number of tags
+ passed in, we can have the following cases:
+
+ 1 - G == N: Store all the N tags to memory.
+
+ 2 - G < N : Warn about having more tags than granules, but write G
+ tags.
+
+ 3 - G > N : This is a "fill tags" operation. We should use the tags
+ as a pattern to fill the granules repeatedly until we have
+ written G tags to memory.
+ */
+
+ size_t g = aarch64_mte_get_tag_granules (addr, length,
+ AARCH64_MTE_GRANULE_SIZE);
+ size_t n = tags.size ();
+
+ if (g < n)
+ warning (_("Got more tags than memory granules. Tags will be "
+ "truncated."));
+ else if (g > n)
+ warning (_("Using tag pattern to fill memory range."));
+
+ if (!target_store_memtags (addr, length, tags,
+ static_cast<int> (memtag_type::allocation)))
+ return false;
+ }
+ return true;
+}
+
+/* Implement the get_memtag gdbarch method. */
+
+static struct value *
+aarch64_linux_get_memtag (struct gdbarch *gdbarch, struct value *address,
+ memtag_type tag_type)
+{
+ gdb_assert (address != nullptr);
+
+ CORE_ADDR addr = value_as_address (address);
+ CORE_ADDR tag = 0;
+
+ /* Get the logical tag or the allocation tag. */
+ if (tag_type == memtag_type::logical)
+ tag = aarch64_mte_get_ltag (addr);
+ else
+ {
+ /* Make sure we are dealing with a tagged address to begin with. */
+ if (!aarch64_linux_tagged_address_p (gdbarch, address))
+ return nullptr;
+
+ gdb::optional<CORE_ADDR> atag = aarch64_mte_get_atag (addr);
+
+ if (!atag.has_value ())
+ return nullptr;
+
+ tag = *atag;
+ }
+
+ /* Convert the tag to a value. */
+ return value_from_ulongest (builtin_type (gdbarch)->builtin_unsigned_int,
+ tag);
+}
+
+/* Implement the memtag_to_string gdbarch method. */
+
+static std::string
+aarch64_linux_memtag_to_string (struct gdbarch *gdbarch, struct value *tag_value)
+{
+ if (tag_value == nullptr)
+ return "";
+
+ CORE_ADDR tag = value_as_address (tag_value);
+
+ return string_printf ("0x%s", phex_nz (tag, sizeof (tag)));
+}
+
+/* AArch64 Linux implementation of the report_signal_info gdbarch
+ hook. Displays information about possible memory tag violations. */
+
+static void
+aarch64_linux_report_signal_info (struct gdbarch *gdbarch,
+ struct ui_out *uiout,
+ enum gdb_signal siggnal)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ if (!tdep->has_mte () || siggnal != GDB_SIGNAL_SEGV)
+ return;
+
+ CORE_ADDR fault_addr = 0;
+ long si_code = 0;
+
+ try
+ {
+ /* Sigcode tells us if the segfault is actually a memory tag
+ violation. */
+ si_code = parse_and_eval_long ("$_siginfo.si_code");
+
+ fault_addr
+ = parse_and_eval_long ("$_siginfo._sifields._sigfault.si_addr");
+ }
+ catch (const gdb_exception_error &exception)
+ {
+ exception_print (gdb_stderr, exception);
+ return;
+ }
+
+ /* If this is not a memory tag violation, just return. */
+ if (si_code != SEGV_MTEAERR && si_code != SEGV_MTESERR)
+ return;
+
+ uiout->text ("\n");
+
+ uiout->field_string ("sigcode-meaning", _("Memory tag violation"));
+
+ /* For synchronous faults, show additional information. */
+ if (si_code == SEGV_MTESERR)
+ {
+ uiout->text (_(" while accessing address "));
+ uiout->field_core_addr ("fault-addr", gdbarch, fault_addr);
+ uiout->text ("\n");
+
+ gdb::optional<CORE_ADDR> atag = aarch64_mte_get_atag (fault_addr);
+ gdb_byte ltag = aarch64_mte_get_ltag (fault_addr);
+
+ if (!atag.has_value ())
+ uiout->text (_("Allocation tag unavailable"));
+ else
+ {
+ uiout->text (_("Allocation tag "));
+ uiout->field_string ("allocation-tag", hex_string (*atag));
+ uiout->text ("\n");
+ uiout->text (_("Logical tag "));
+ uiout->field_string ("logical-tag", hex_string (ltag));
+ }
+ }
+ else
+ {
+ uiout->text ("\n");
+ uiout->text (_("Fault address unavailable"));
+ }
+}
+
static void
aarch64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
data associated with the address. */
set_gdbarch_significant_addr_bit (gdbarch, 56);
+ /* MTE-specific settings and hooks. */
+ if (tdep->has_mte ())
+ {
+ /* Register a hook for checking if an address is tagged or not. */
+ set_gdbarch_tagged_address_p (gdbarch, aarch64_linux_tagged_address_p);
+
+ /* Register a hook for checking if there is a memory tag match. */
+ set_gdbarch_memtag_matches_p (gdbarch,
+ aarch64_linux_memtag_matches_p);
+
+ /* Register a hook for setting the logical/allocation tags for
+ a range of addresses. */
+ set_gdbarch_set_memtags (gdbarch, aarch64_linux_set_memtags);
+
+ /* Register a hook for extracting the logical/allocation tag from an
+ address. */
+ set_gdbarch_get_memtag (gdbarch, aarch64_linux_get_memtag);
+
+ /* Set the allocation tag granule size to 16 bytes. */
+ set_gdbarch_memtag_granule_size (gdbarch, AARCH64_MTE_GRANULE_SIZE);
+
+ /* Register a hook for converting a memory tag to a string. */
+ set_gdbarch_memtag_to_string (gdbarch, aarch64_linux_memtag_to_string);
+
+ set_gdbarch_report_signal_info (gdbarch,
+ aarch64_linux_report_signal_info);
+ }
+
/* Initialize the aarch64_linux_record_tdep. */
/* These values are the size of the type that will be used in a system
call. They are obtained from Linux Kernel source. */
set_gdbarch_gcc_target_options (gdbarch, aarch64_linux_gcc_target_options);
}
+#if GDB_SELF_TEST
+
+namespace selftests {
+
+/* Verify functions to read and write logical tags. */
+
+static void
+aarch64_linux_ltag_tests (void)
+{
+ /* We have 4 bits of tags, but we test writing all the bits of the top
+ byte of address. */
+ for (int i = 0; i < 1 << 8; i++)
+ {
+ CORE_ADDR addr = ((CORE_ADDR) i << 56) | 0xdeadbeef;
+ SELF_CHECK (aarch64_mte_get_ltag (addr) == (i & 0xf));
+
+ addr = aarch64_mte_set_ltag (0xdeadbeef, i);
+ SELF_CHECK (addr = ((CORE_ADDR) (i & 0xf) << 56) | 0xdeadbeef);
+ }
+}
+
+} // namespace selftests
+#endif /* GDB_SELF_TEST */
+
void _initialize_aarch64_linux_tdep ();
void
_initialize_aarch64_linux_tdep ()
{
gdbarch_register_osabi (bfd_arch_aarch64, 0, GDB_OSABI_LINUX,
aarch64_linux_init_abi);
+
+#if GDB_SELF_TEST
+ selftests::register_test ("aarch64-linux-tagged-address",
+ selftests::aarch64_linux_ltag_tests);
+#endif
}
projects / binutils-gdb.git / blobdiff