Patchwork gdb: ADI support

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Submitter Weimin Pan
Date June 14, 2017, 12:05 a.m.
Message ID <1497398744-107551-1-git-send-email-weimin.pan@oracle.com>
Download mbox | patch
Permalink /patch/21002/
State New
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Comments

Weimin Pan - June 14, 2017, 12:05 a.m.
The M7 processor supports an Application Data Integrity (ADI) feature
   that detects invalid data accesses.  When software allocates data, it
   chooses a 4-bit version number, sets the version in the upper 4 bits
   of the 64-bit pointer to that data, and stores the 4-bit version in
   every cacheline of the object.  Hardware saves the latter in spare
   bits in the cache and memory hierarchy. On each load and store, the
   processor compares the upper 4 VA (virtual address) bits to the
   cacheline's version. If there is a mismatch, the processor generates
   a version mismatch trap which can be either precise or disrupting.
   The trap is an error condition which the kernel delivers to the process
   as a SIGSEGV signal.

   The upper 4 bits of the VA represent a version and are not part of the
   true address.  The processor clears these bits and sign extends bit 59
   to generate the true address.

   Note that 32-bit applications cannot use ADI.

   This patch adds ADI support in gdb which allows the user to examine
   current version tags and assign new version tags in the program.
   It also catches and reports precise or disrupting memory corruption
   traps.

Tested in sparc64-linux-gnu. No regressions.

gdb/ChangeLog:
2017-06-13  Weimin Pan  <weimin.pan@oracle.com>

	* sparc64-tdep.h: (adi_normalize_address): New export.
	* sparc64-adi-tdep.c: New file.
	* Makefile.in (ALLDEPFILES): Add sparc64-adi-tdep.c.
	* configure.tgt: Add sparc64-adi-tdep.o.
	* sparc64-linux-nat.c:
	(sparc64_linux_watchpoint_addr_within_range): New function.
	(_initialize_sparc64_linux_nat): Register sparc64_linux_watchpoint_addr_within_range.
	* sparc64-linux-tdep.c: Include <adi.h>.
	(sparc64_linux_handle_segmentation_fault): New function.
	(sparc64_linux_init_abi): Register sparc64_linux_handle_segmentation_fault
	* sparc64-tdep.c: (sparc64_pstate_type): Replace PID1 with MCDE.
gdb/doc/ChangeLog:
2017-06-13  Weimin Pan  <weimin.pan@oracle.com>
	* gdb.texinfo (Architectures): Add new Sparc64 section to document ADI support.
---
 gdb/Makefile.in          |    2 +
 gdb/configure.tgt        |    1 +
 gdb/doc/gdb.texinfo      |   84 ++++++++
 gdb/sparc64-adi-tdep.c   |  476 ++++++++++++++++++++++++++++++++++++++++++++++
 gdb/sparc64-linux-nat.c  |   15 ++
 gdb/sparc64-linux-tdep.c |   49 +++++
 gdb/sparc64-tdep.c       |    2 +-
 gdb/sparc64-tdep.h       |    2 +
 8 files changed, 630 insertions(+), 1 deletions(-)
 create mode 100644 gdb/sparc64-adi-tdep.c
Eli Zaretskii - June 14, 2017, 3:23 p.m.
> From: Weimin Pan <weimin.pan@oracle.com>
> Date: Tue, 13 Jun 2017 19:05:44 -0500
> 
> gdb/ChangeLog:
> 2017-06-13  Weimin Pan  <weimin.pan@oracle.com>
> 
> 	* sparc64-tdep.h: (adi_normalize_address): New export.
> 	* sparc64-adi-tdep.c: New file.
> 	* Makefile.in (ALLDEPFILES): Add sparc64-adi-tdep.c.
> 	* configure.tgt: Add sparc64-adi-tdep.o.
> 	* sparc64-linux-nat.c:
> 	(sparc64_linux_watchpoint_addr_within_range): New function.
> 	(_initialize_sparc64_linux_nat): Register sparc64_linux_watchpoint_addr_within_range.
> 	* sparc64-linux-tdep.c: Include <adi.h>.
> 	(sparc64_linux_handle_segmentation_fault): New function.
> 	(sparc64_linux_init_abi): Register sparc64_linux_handle_segmentation_fault
> 	* sparc64-tdep.c: (sparc64_pstate_type): Replace PID1 with MCDE.
> gdb/doc/ChangeLog:
> 2017-06-13  Weimin Pan  <weimin.pan@oracle.com>
> 	* gdb.texinfo (Architectures): Add new Sparc64 section to document ADI support.

Thanks.  See below some comments about the documentation part:

> +@node Sparc64
> +@subsection Sparc64
> +@cindex Sparc64 support
> +@subsubsection ADI Support

I'd add an index entry for "Application Data Integrity" here.

> +The M7 processor supports an Application Data Integrity (ADI) feature that 
> +detects invalid data accesses. When software allocates memory and enables ADI on the 

Please leave two spaces between sentences, here and elsewhere.  Also,
please refill the paragraphs so that they are shorter than 80 cloumns.

> +@item adi examine Command

I think you should remove the "Command" part there.

> +The adi examine command displays the value of one ADI version tag per cacheline. 
       ^^^^^^^^^^^
This should be in @code{..}

> +It has the following command syntax: 
> +
> +@cindex examining memory

There's no need for this index entry here, because this part of the
text doesn't describe the commands that examine memory.  (There are
other such index entries in your patch; they should all be removed.)

> +@table @code
> +@kindex x @r{(examine memory)}
> +@itemx adi (examine | x) [ / @var{n} ] @var{addr}

I think the @kindex entry here should be removed.  Instead, you should
have a "@kindex adi examine" earlier, where you mention the command
for the first time.

> +@table @r
> +@item @var{n}, the byte count

This should not be a @table, and you don't need the @item.  Instead,
there should be plain text describing the command arguments.

> +@item adi assign Command

Please add an index entry here about "adi assign".

> +@cindex examining memory
> +@table @code
> +@kindex x @r{(examine memory)}
> +@itemx adi (assign | a) [ / @var{n} ] @var{addr} = @var{tag}
> +@end table
> +
> +@table @r
> +@item @var{n}, the byte count

Same comments as above for "adi examine".

Do we need a NEWS entry for these new commands?
Weimin Pan - June 14, 2017, 5:15 p.m.
On 6/14/2017 8:23 AM, Eli Zaretskii wrote:
>> From: Weimin Pan <weimin.pan@oracle.com>
>> Date: Tue, 13 Jun 2017 19:05:44 -0500
>>
>> gdb/ChangeLog:
>> 2017-06-13  Weimin Pan  <weimin.pan@oracle.com>
>>
>> 	* sparc64-tdep.h: (adi_normalize_address): New export.
>> 	* sparc64-adi-tdep.c: New file.
>> 	* Makefile.in (ALLDEPFILES): Add sparc64-adi-tdep.c.
>> 	* configure.tgt: Add sparc64-adi-tdep.o.
>> 	* sparc64-linux-nat.c:
>> 	(sparc64_linux_watchpoint_addr_within_range): New function.
>> 	(_initialize_sparc64_linux_nat): Register sparc64_linux_watchpoint_addr_within_range.
>> 	* sparc64-linux-tdep.c: Include <adi.h>.
>> 	(sparc64_linux_handle_segmentation_fault): New function.
>> 	(sparc64_linux_init_abi): Register sparc64_linux_handle_segmentation_fault
>> 	* sparc64-tdep.c: (sparc64_pstate_type): Replace PID1 with MCDE.
>> gdb/doc/ChangeLog:
>> 2017-06-13  Weimin Pan  <weimin.pan@oracle.com>
>> 	* gdb.texinfo (Architectures): Add new Sparc64 section to document ADI support.
> Thanks.  See below some comments about the documentation part:
>
>> +@node Sparc64
>> +@subsection Sparc64
>> +@cindex Sparc64 support
>> +@subsubsection ADI Support
> I'd add an index entry for "Application Data Integrity" here.

Done,  added "@cindex Application Data Integrity".

>> +The M7 processor supports an Application Data Integrity (ADI) feature that
>> +detects invalid data accesses. When software allocates memory and enables ADI on the
> Please leave two spaces between sentences, here and elsewhere.  Also,
> please refill the paragraphs so that they are shorter than 80 cloumns.

Checked and corrected.

>> +@item adi examine Command
> I think you should remove the "Command" part there.

Done for both "adi examine" and "adi assign".

>> +The adi examine command displays the value of one ADI version tag per cacheline.
>         ^^^^^^^^^^^
> This should be in @code{..}

Done for both.

>> +It has the following command syntax:
>> +
>> +@cindex examining memory
> There's no need for this index entry here, because this part of the
> text doesn't describe the commands that examine memory.  (There are
> other such index entries in your patch; they should all be removed.)

OK, 2 of such entries removed.

>> +@table @code
>> +@kindex x @r{(examine memory)}
>> +@itemx adi (examine | x) [ / @var{n} ] @var{addr}
> I think the @kindex entry here should be removed.  Instead, you should
> have a "@kindex adi examine" earlier, where you mention the command
> for the first time.

OK, moved it next to "@item adi examine".

>> +@table @r
>> +@item @var{n}, the byte count
> This should not be a @table, and you don't need the @item.  Instead,
> there should be plain text describing the command arguments.

OK, @table and @item removed.

>> +@item adi assign Command
> Please add an index entry here about "adi assign".
>
>> +@cindex examining memory
>> +@table @code
>> +@kindex x @r{(examine memory)}
>> +@itemx adi (assign | a) [ / @var{n} ] @var{addr} = @var{tag}
>> +@end table
>> +
>> +@table @r
>> +@item @var{n}, the byte count
> Same comments as above for "adi examine".

Done.

> Do we need a NEWS entry for these new commands?

Is there any guideline as to when such an entry should be added?
I can add something like this:

         * NEWS: Add "adi examine" and "adi assign" commands for printing
         and modifying values of ADI version tag on Sparc64 platform.

Thanks for your comments.
Eli Zaretskii - June 14, 2017, 7:18 p.m.
> Cc: gdb-patches@sourceware.org
> From: Wei-min Pan <weimin.pan@oracle.com>
> Date: Wed, 14 Jun 2017 10:15:28 -0700
> 
> > Do we need a NEWS entry for these new commands?
> 
> Is there any guideline as to when such an entry should be added?

Basically, any significant change in user-visible behavior should be
mentioned in NEWS.  New commands certainly belong to that class.

> I can add something like this:
> 
>          * NEWS: Add "adi examine" and "adi assign" commands for printing
>          and modifying values of ADI version tag on Sparc64 platform.

This is a ChangeLog entry.  The actual text in NEWS should go under
the "New commands" section, and it should say something like

  adi examine
    Examine ADI version tags.

  adi assign
    Assign new ADI version tags.

You will see similar examples where we announce other new commands.
Ivo Raisr - June 14, 2017, 7:53 p.m.
On 14.6.2017 02:05, Weimin Pan wrote:
>    The M7 processor supports an Application Data Integrity (ADI) feature
>    that detects invalid data accesses.  When software allocates data, it
>    chooses a 4-bit version number, sets the version in the upper 4 bits
>    of the 64-bit pointer to that data, and stores the 4-bit version in
>    every cacheline of the object.  Hardware saves the latter in spare
>    bits in the cache and memory hierarchy. On each load and store, the
>    processor compares the upper 4 VA (virtual address) bits to the
>    cacheline's version. If there is a mismatch, the processor generates
>    a version mismatch trap which can be either precise or disrupting.
>    The trap is an error condition which the kernel delivers to the process
>    as a SIGSEGV signal.
> 
>    The upper 4 bits of the VA represent a version and are not part of the
>    true address.  The processor clears these bits and sign extends bit 59
>    to generate the true address.
> 
>    Note that 32-bit applications cannot use ADI.
> 
>    This patch adds ADI support in gdb which allows the user to examine
>    current version tags and assign new version tags in the program.
>    It also catches and reports precise or disrupting memory corruption
>    traps.
> 
> Tested in sparc64-linux-gnu. No regressions.
> 
> gdb/ChangeLog:
> 2017-06-13  Weimin Pan  <weimin.pan@oracle.com>
> 
> 	* sparc64-tdep.h: (adi_normalize_address): New export.
> 	* sparc64-adi-tdep.c: New file.
> 	* Makefile.in (ALLDEPFILES): Add sparc64-adi-tdep.c.
> 	* configure.tgt: Add sparc64-adi-tdep.o.
> 	* sparc64-linux-nat.c:
> 	(sparc64_linux_watchpoint_addr_within_range): New function.
> 	(_initialize_sparc64_linux_nat): Register sparc64_linux_watchpoint_addr_within_range.
> 	* sparc64-linux-tdep.c: Include <adi.h>.
> 	(sparc64_linux_handle_segmentation_fault): New function.
> 	(sparc64_linux_init_abi): Register sparc64_linux_handle_segmentation_fault
> 	* sparc64-tdep.c: (sparc64_pstate_type): Replace PID1 with MCDE.
> gdb/doc/ChangeLog:
> 2017-06-13  Weimin Pan  <weimin.pan@oracle.com>
> 	* gdb.texinfo (Architectures): Add new Sparc64 section to document ADI support.

Please note that the patch has been reviewed internally by other Oracle
folks, mainly from the functional point of view. We would be glad to
have more eyeballs reviewing the patch, especially from the formal point
of view.

I.

Patch

diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index 5e5fcaa..a6b0d99 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -772,6 +772,7 @@  ALL_64_TARGET_OBS = \
 	ia64-tdep.o \
 	ia64-vms-tdep.o \
 	mips64-obsd-tdep.o \
+	sparc64-adi-tdep.o \
 	sparc64-fbsd-tdep.o \
 	sparc64-linux-tdep.o \
 	sparc64-nbsd-tdep.o \
@@ -2660,6 +2661,7 @@  ALLDEPFILES = \
 	sparc-sol2-nat.c \
 	sparc-sol2-tdep.c \
 	sparc-tdep.c \
+	sparc64-adi-tdep.c \
 	sparc64-fbsd-nat.c \
 	sparc64-fbsd-tdep.c \
 	sparc64-linux-nat.c \
diff --git a/gdb/configure.tgt b/gdb/configure.tgt
index fdcb7b1..0519c62 100644
--- a/gdb/configure.tgt
+++ b/gdb/configure.tgt
@@ -548,6 +548,7 @@  sparc64-*-linux*)
 	gdb_target_obs="sparc64-tdep.o sparc64-sol2-tdep.o sol2-tdep.o \
 			sparc64-linux-tdep.o sparc-tdep.o sparc-sol2-tdep.o \
 			sparc-linux-tdep.o solib-svr4.o linux-tdep.o \
+			sparc64-adi-tdep.o \
 			ravenscar-thread.o sparc-ravenscar-thread.o"
 	build_gdbserver=yes
 	;;
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 8d7a1c9..a34bd87 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -22465,6 +22465,7 @@  all uses of @value{GDBN} with the architecture, both native and cross.
 * SPU::                Cell Broadband Engine SPU architecture
 * PowerPC::
 * Nios II::
+* Sparc64::
 @end menu
 
 @node AArch64
@@ -22849,6 +22850,89 @@  target code in @value{GDBN}.
 Show the current setting of Nios II debugging messages.
 @end table
 
+@node Sparc64
+@subsection Sparc64
+@cindex Sparc64 support
+@subsubsection ADI Support
+
+The M7 processor supports an Application Data Integrity (ADI) feature that 
+detects invalid data accesses. When software allocates memory and enables ADI on the 
+allocated memory, it chooses a 4-bit version number, sets the version in the upper 4 bits 
+of the 64-bit pointer to that data, and stores the 4-bit version in every cacheline of 
+that data. Hardware saves the latter in spare bits in the cache and memory hierarchy. 
+On each load and store, the processor compares the upper 4 VA (virtual address) bits to 
+the cacheline's version.  If there is a mismatch, the processor generates a version 
+mismatch trap which can be either precise or disrupting. The trap is an error condition 
+which the kernel delivers to the process as a SIGSEGV signal.
+
+Note that only 64-bit applications can use ADI and need to be built with
+ADI-enabled.
+
+Values of the ADI version tags, which are in granularity of a 
+cacheline (64 bytes), can be viewed or modified. 
+
+
+@table @code
+@item adi examine Command
+
+The adi examine command displays the value of one ADI version tag per cacheline. 
+It has the following command syntax: 
+
+@cindex examining memory
+@table @code
+@kindex x @r{(examine memory)}
+@itemx adi (examine | x) [ / @var{n} ] @var{addr}
+@end table
+
+@table @r
+@item @var{n}, the byte count
+The count is a decimal integer specifying the number in bytes; the default is 1.  It specifies
+how much ADI version information, at the ratio of 1:ADI block size, to display. 
+
+@item @var{addr}, starting display address
+@var{addr} is the address in user address space where you want @value{GDBN} to begin displaying
+the ADI version tags. 
+@end table
+
+Below is an example of displaying ADI versions of variable "shmaddr".
+
+@smallexample
+(@value{GDBP}) adi x/100 shmaddr
+   0xfff800010002c000:     0 0
+@end smallexample
+
+@item adi assign Command
+
+The adi assign command is used to assign new ADI version tag 
+to an address. It has the following command syntax:
+
+@cindex examining memory
+@table @code
+@kindex x @r{(examine memory)}
+@itemx adi (assign | a) [ / @var{n} ] @var{addr} = @var{tag}
+@end table
+
+@table @r
+@item @var{n}, the byte count
+The count is a decimal integer specifying the number in bytes; the default is 1.  It specifies
+how much ADI version information, at the ratio of 1:ADI block size, to modify. 
+
+@item @var{addr}, starting display address
+@var{addr} is the address in user address space where you want @value{GDBN} 
+to begin modifying the ADI version tags. 
+@item @var{tag}, the new ADI version tag
+@end table
+
+For example, do the following to modify then verify ADI versions of variable "shmaddr":
+
+@smallexample
+(@value{GDBP}) adi a/100 shmaddr = 7
+(@value{GDBP}) adi x/100 shmaddr
+   0xfff800010002c000:     7 7
+@end smallexample
+
+@end table
+
 @node Controlling GDB
 @chapter Controlling @value{GDBN}
 
diff --git a/gdb/sparc64-adi-tdep.c b/gdb/sparc64-adi-tdep.c
new file mode 100644
index 0000000..b9ef61c
--- /dev/null
+++ b/gdb/sparc64-adi-tdep.c
@@ -0,0 +1,476 @@ 
+/* Target-dependent code for Sparc64.
+
+   Copyright (C) 2017 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <adi.h>
+#include "defs.h"
+#include "inferior.h"
+#include "gdbcmd.h"
+#include "auxv.h"
+
+/* The M7 processor supports an Application Data Integrity (ADI) feature
+   that detects invalid data accesses.  When software allocates memory and 
+   enables ADI on the allocated memory, it chooses a 4-bit version number, 
+   sets the version in the upper 4 bits of the 64-bit pointer to that data, 
+   and stores the 4-bit version in every cacheline of the object.  Hardware 
+   saves the latter in spare bits in the cache and memory hierarchy. On each 
+   load and store, the processor compares the upper 4 VA (virtual address) bits 
+   to the cacheline's version. If there is a mismatch, the processor generates
+   a version mismatch trap which can be either precise or disrupting.
+   The trap is an error condition which the kernel delivers to the process
+   as a SIGSEGV signal.
+
+   The upper 4 bits of the VA represent a version and are not part of the
+   true address.  The processor clears these bits and sign extends bit 59
+   to generate the true address.
+
+   Note that 32-bit applications cannot use ADI. */
+
+
+#define MAX_PROC_NAME_SIZE sizeof("/proc/99999/lwp/9999/adi/lstatus")
+
+/* ADI command list.  */
+static struct cmd_list_element *sparc64adilist = NULL;
+
+/* Current ADI stat settings.  */
+static struct
+{
+  /* The ADI block size.  */
+  unsigned long blksize;
+
+  /* Number of bits used for an ADI version tag which can be
+   * used together with the shift value for an ADI version tag
+   * to encode or extract the ADI version value in a pointer.  */
+  unsigned long nbits;
+
+  /* The maximum ADI version tag value supported.  */
+  int max_version;
+
+  /* ADI version tag file.  */
+  int tag_fd;
+
+  /* Last ADI address examined.  */
+  CORE_ADDR last_vaddr;
+
+  /* Last specified examination count.  */
+  int last_cnt;
+
+  /* ADI availability check has been done.  */
+  bool checked_avail;
+
+  /* ADI is available.  */
+  bool is_avail;
+
+} adi_stat;
+
+
+static void
+info_adi_command (char *args, int from_tty)
+{
+  printf_unfiltered ("\"adi\" must be followed by \"examine\" "
+                     "or \"assign\".\n");
+  help_list (sparc64adilist, "adi ", all_commands, gdb_stdout);
+}
+
+static bool
+arch_is_64bit (void)
+{
+  struct gdbarch *gdbarch = get_frame_arch (get_current_frame ());
+  return gdbarch_bfd_arch_info (gdbarch)->bits_per_word == 64;
+
+}
+
+static int
+parse_byte_count (const char **sptr)
+{
+  const char *p = *sptr;
+  int cnt = 1;
+  if (*p == '-')
+    {
+      cnt = -1;
+      p++;
+    }
+  if (*p >= '0' && *p <= '9')
+    cnt *= atoi (p);
+  while (*p >= '0' && *p <= '9')
+    p++;
+  while (*p == ' ' || *p == '\t')
+    p++;
+  *sptr = p;
+
+  if (cnt <= 0)
+    error (_("Byte count should have a positive value."));
+
+  return cnt;
+}
+
+static CORE_ADDR
+parse_address (const char *exp)
+{
+  expression_up expr = parse_expression (exp);
+  struct value *val = evaluate_expression (expr.get ());
+  if (TYPE_CODE (value_type (val)) == TYPE_CODE_REF)
+    val = coerce_ref (val);
+  if (TYPE_CODE (value_type (val)) == TYPE_CODE_FUNC
+      && VALUE_LVAL (val) == lval_memory)
+    return value_address (val);
+  else
+    return value_as_address (val);
+}
+
+/* Read attributes of a maps entry in /proc/[pid]/adi/maps.  */
+
+static void
+read_maps_entry (const char *line,
+              ULONGEST *addr, ULONGEST *endaddr)
+{
+  const char *p = line;
+
+  *addr = strtoulst (p, &p, 16);
+  if (*p == '-')
+    p++;
+
+  *endaddr = strtoulst (p, &p, 16);
+}
+
+/* Check if ADI is available.  */
+
+static bool
+adi_available (void)
+{
+  if (adi_stat.checked_avail)
+    return adi_stat.is_avail;
+
+  adi_stat.checked_avail = true;
+  if (!arch_is_64bit ())
+    return false;
+  if (target_auxv_search (&current_target, AT_ADI_BLKSZ, &adi_stat.blksize) <= 0)
+    return false;
+  target_auxv_search (&current_target, AT_ADI_NBITS, &adi_stat.nbits);
+  adi_stat.max_version = (1 << adi_stat.nbits) - 2;
+  adi_stat.is_avail = true;
+
+  return adi_stat.is_avail;
+}
+
+#if 0
+/* Extract version tag from a versioned address.  */
+
+int adi_extract_version (CORE_ADDR versioned_addr)
+{
+  return ((unsigned long)versioned_addr) >> (64 - adi_stat.nbits);
+}
+#endif
+
+/* Normalize a versioned address - a VA with ADI bits (63-60) set.  */
+
+CORE_ADDR
+adi_normalize_address (CORE_ADDR addr)
+{
+  if (adi_stat.nbits)
+    return ((CORE_ADDR)(((long)addr << adi_stat.nbits) >> adi_stat.nbits));
+  return addr;
+}
+
+/* Align a normalized address - a VA with bit 59 sign extended into ADI bits.  */
+
+static CORE_ADDR
+adi_align_address (CORE_ADDR naddr)
+{
+    return (naddr - (naddr % adi_stat.blksize)) / adi_stat.blksize;
+}
+
+/* Convert a byte count to count at a ratio of 1:adi_blksz.  */
+
+static int
+adi_convert_byte_count (CORE_ADDR naddr, int nbytes, CORE_ADDR locl)
+{
+    return ((naddr + nbytes + adi_stat.blksize - 1) / adi_stat.blksize) - locl;
+}
+
+/* The /proc/[pid]/adi/tag file, which allows gdb to get/set ADI
+   version in a target process, maps linearly to the address space
+   of the target process at a ratio of 1:adi_blksz.
+
+   A read (or write) at offset K in the file returns (or modifies)
+   the ADI version tag stored in the cacheline containing address
+   K * adi_blksz, encoded as 1 version tag per byte.  The allowed
+   version tag values are between 0 and adi_stat.max_version.  */
+
+static int
+adi_tag_fd (void)
+{
+  if (adi_stat.tag_fd != 0)
+    return adi_stat.tag_fd;
+
+  char cl_name[MAX_PROC_NAME_SIZE];
+  pid_t pid = ptid_get_pid (inferior_ptid);
+  snprintf (cl_name, sizeof(cl_name), "/proc/%d/adi/tag", pid);
+  adi_stat.tag_fd = open (cl_name, O_RDWR|O_EXCL|O_CLOEXEC);
+
+  return adi_stat.tag_fd;
+}
+
+/* Check if an address set is ADI enabled, using /proc/[pid]/adi/maps
+   which was exported by the kernel and contains the currently ADI
+   mapped memory regions and their access permissions.  */
+
+static bool
+adi_is_addr_mapped (CORE_ADDR vaddr, size_t cnt)
+{
+  char filename[MAX_PROC_NAME_SIZE];
+  size_t i = 0;
+
+  pid_t pid = ptid_get_pid (inferior_ptid);
+  snprintf (filename, sizeof filename, "/proc/%d/adi/maps", pid);
+  char *data = target_fileio_read_stralloc (NULL, filename);
+  if (data)
+    {
+      struct cleanup *cleanup = make_cleanup (xfree, data);
+      char *line;
+      for (line = strtok (data, "\n"); line; line = strtok (NULL, "\n"))
+        {
+          ULONGEST addr, endaddr;
+
+          read_maps_entry (line, &addr, &endaddr);
+
+          while (((vaddr + i) * adi_stat.blksize) >= addr
+                 && ((vaddr + i) * adi_stat.blksize) < endaddr)
+            {
+              if (++i == cnt)
+                {
+                  do_cleanups (cleanup);
+                  return true;
+                }
+            }
+        }
+        do_cleanups (cleanup);
+      }
+    else
+      warning (_("unable to open /proc file '%s'"), filename);
+
+  return false;
+}
+
+/* Read ADI version tag value for memory locations starting at "vaddr"
+   for "size" number of bytes.  */
+
+static int
+adi_read_versions (CORE_ADDR vaddr, size_t size, unsigned char *tags)
+{
+  int fd = adi_tag_fd ();
+  if (fd == -1)
+    return -1;
+
+  if (!adi_is_addr_mapped (vaddr, size))
+    error(_("Address at 0x%lx is not in ADI maps"), vaddr*adi_stat.blksize);
+
+  return pread64 (fd, tags, size, vaddr);
+}
+
+/* Write ADI version tag for memory locations starting at "vaddr" for
+ "size" number of bytes to "tags".  */
+
+static int
+adi_write_versions (CORE_ADDR vaddr, size_t size, unsigned char *tags)
+{
+  int fd = adi_tag_fd ();
+  if (fd == -1)
+    return -1;
+
+  if (!adi_is_addr_mapped (vaddr, size))
+    error(_("Address at 0x%lx is not in ADI maps"), vaddr*adi_stat.blksize);
+
+  return pwrite64 (fd, tags, size, vaddr);
+}
+
+/* Print ADI version tag value in "tags" for memory locations starting
+   at "vaddr" with number of "cnt".  */
+
+static void
+adi_print_versions (CORE_ADDR vaddr, size_t cnt, unsigned char *tags)
+{
+  int v_idx = 0;
+  const int maxelts = 8;  /* # of elements per line */
+
+  while (cnt > 0)
+    {
+      QUIT;
+      printf_filtered ("0x%016lx:\t", vaddr * adi_stat.blksize);
+      for (int i = maxelts; i > 0 && cnt > 0; i--, cnt--)
+        {
+          if (tags[v_idx] == 0xff)    /* no version tag */
+            printf_filtered ("- ");
+          else
+            printf_filtered ("%1X ", tags[v_idx]);
+          ++v_idx;
+        }
+      printf_filtered ("\n");
+      gdb_flush (gdb_stdout);
+      vaddr += maxelts;
+    }
+}
+
+static void
+do_examine (CORE_ADDR start, int bcnt)
+{
+  CORE_ADDR vaddr = adi_normalize_address (start);
+  struct cleanup *cleanup;
+
+  CORE_ADDR vstart = adi_align_address (vaddr);
+  int cnt = adi_convert_byte_count (vaddr, bcnt, vstart);
+  unsigned char *buf = (unsigned char *) xmalloc (cnt);
+  cleanup = make_cleanup (xfree, buf);
+  int read_cnt = adi_read_versions (vstart, cnt, buf);
+  if (read_cnt == -1)
+    error (_("No ADI information"));
+  else if (read_cnt < cnt)
+    error(_("No ADI information at 0x%lx"), vaddr);
+
+  adi_print_versions(vstart, cnt, buf);
+
+  do_cleanups (cleanup);
+}
+
+static void
+do_assign (CORE_ADDR start, size_t bcnt, int version)
+{
+  CORE_ADDR vaddr = adi_normalize_address (start);
+
+  CORE_ADDR vstart = adi_align_address (vaddr);
+  int cnt = adi_convert_byte_count (vaddr, bcnt, vstart);
+  unsigned char *buf = (unsigned char *) xmalloc (cnt);
+  memset(buf, version, cnt);
+
+  int set_cnt = adi_write_versions (vstart, cnt, buf);
+  xfree (buf);
+
+  if (set_cnt == -1)
+    error (_("No ADI information"));
+  else if (set_cnt < cnt)
+    error(_("No ADI information at 0x%lx"), vaddr);
+
+}
+
+/* ADI examine version tag command.
+
+   Command syntax:
+
+     adi (examine|x)/count <addr> */
+
+static void
+adi_examine_command (char *args, int from_tty)
+{
+  /* make sure program is active and adi is available */
+  if (!target_has_execution)
+    error (_("ADI command requires a live process/thread"));
+
+  if (!adi_available ())
+    error (_("No ADI information"));
+
+  int cnt = adi_stat.last_cnt? adi_stat.last_cnt : 1;
+  const char *p = args;
+  if (p && *p == '/')
+    {
+      p++;
+      cnt = parse_byte_count (&p);
+    }
+
+  CORE_ADDR next_address = adi_stat.last_vaddr ? adi_stat.last_vaddr : 0;
+  if (p != 0 && *p != 0)
+    next_address = parse_address (p);
+  else if (!adi_stat.last_cnt)
+    error (_("Usage: adi examine|x[/count] <addr>"));
+
+  if (next_address)
+    do_examine(next_address, cnt);
+
+  adi_stat.last_cnt = cnt;
+  adi_stat.last_vaddr = next_address + adi_stat.blksize * cnt;
+}
+
+/* ADI assign version tag command.
+
+   Command syntax:
+
+     adi (assign|a)/count <addr> = <version>  */
+
+static void
+adi_assign_command (char *args, int from_tty)
+{
+  /* make sure program is active and adi is available */
+  if (!target_has_execution)
+    error (_("ADI command requires a live process/thread"));
+
+  if (!adi_available ())
+    error (_("No ADI information"));
+
+  const char *exp = args;
+  if (exp == 0)
+    error_no_arg (_("Usage: adi assign|a[/count] <addr> = <version>"));
+
+  char *q = (char *) strchr (exp, '=');
+  if (q)
+    *q++ = 0;
+  else
+    error (_("Usage: adi assign|a[/count] <addr> = <version>"));
+
+  size_t cnt = 1;
+  const char *p = exp;
+  if (exp && *exp == '/')
+    {
+      p = exp + 1;
+      cnt = parse_byte_count (&p);
+    }
+
+  CORE_ADDR next_address = 0;
+  if (p != 0 && *p != 0)
+    next_address = parse_address (p);
+  else
+    error (_("Usage: adi assign|a[/count] <addr> = <version>"));
+
+  int version = 0;
+  if (q)           /* parse version tag */
+    {
+      expression_up expr = parse_expression (q);
+      struct value *val = evaluate_expression (expr.get ());
+      version = value_as_long (val);
+      if (version < 0 || version > adi_stat.max_version)
+        error (_("Invalid ADI version tag %d"), version);
+    }
+
+  do_assign(next_address, cnt, version);
+}
+
+extern initialize_file_ftype _initialize_sparc64_adi_tdep; /* -Wmissing-prototypes */
+
+void
+_initialize_sparc64_adi_tdep (void)
+{
+
+  add_prefix_cmd ("adi", class_support, info_adi_command,
+                  _("ADI version related commands."),
+                  &sparc64adilist, "adi ", 0, &cmdlist);
+  add_cmd ("examine", class_support, adi_examine_command,
+           _("Examine ADI versions."), &sparc64adilist);
+  add_alias_cmd ("x", "examine", no_class, 1, &sparc64adilist);
+  add_cmd ("assign", class_support, adi_assign_command,
+           _("Assign ADI versions."), &sparc64adilist);
+
+}
+
diff --git a/gdb/sparc64-linux-nat.c b/gdb/sparc64-linux-nat.c
index 638aa29..01adcd6 100644
--- a/gdb/sparc64-linux-nat.c
+++ b/gdb/sparc64-linux-nat.c
@@ -69,6 +69,18 @@  fill_fpregset (const struct regcache *regcache,
   sparc64_collect_fpregset (&sparc64_bsd_fpregmap, regcache, regnum, fpregs);
 }
 
+/* Implement the "to_watchpoint_addr_within_range" target_ops method.  */
+
+static int
+sparc64_linux_watchpoint_addr_within_range (struct target_ops *target,
+					    CORE_ADDR addr,
+					    CORE_ADDR start, int length)
+{
+  start = adi_normalize_address (start);
+  addr = adi_normalize_address (addr);
+  return (start <= addr) && (start + length - 1 >= addr);
+}
+
 /* Provide a prototype to silence -Wmissing-prototypes.  */
 void _initialize_sparc64_linux_nat (void);
 
@@ -86,6 +98,9 @@  _initialize_sparc64_linux_nat (void)
   t->to_fetch_registers = sparc_fetch_inferior_registers;
   t->to_store_registers = sparc_store_inferior_registers;
 
+  t->to_watchpoint_addr_within_range =
+    sparc64_linux_watchpoint_addr_within_range;
+
   /* Register the target.  */
   linux_nat_add_target (t);
 
diff --git a/gdb/sparc64-linux-tdep.c b/gdb/sparc64-linux-tdep.c
index 814bc29..17eb8c5 100644
--- a/gdb/sparc64-linux-tdep.c
+++ b/gdb/sparc64-linux-tdep.c
@@ -32,6 +32,7 @@ 
 #include "tramp-frame.h"
 #include "xml-syscall.h"
 #include "linux-tdep.h"
+#include <adi.h>
 
 /* The syscall's XML filename for sparc 64-bit.  */
 #define XML_SYSCALL_FILENAME_SPARC64 "syscalls/sparc64-linux.xml"
@@ -104,6 +105,52 @@  sparc64_linux_sigframe_init (const struct tramp_frame *self,
     }
   trad_frame_set_id (this_cache, frame_id_build (base, func));
 }
+
+/* sparc64 GNU/Linux implementation of the handle_segmentation_fault
+   gdbarch hook.
+   Displays information related to ADI memory corruptions.  */
+
+void
+sparc64_linux_handle_segmentation_fault (struct gdbarch *gdbarch,
+				      struct ui_out *uiout)
+{
+  if (gdbarch_bfd_arch_info (gdbarch)->bits_per_word != 64)
+    return;
+
+  CORE_ADDR addr = 0;
+  long si_code = 0;
+
+  TRY
+    {
+      /* Evaluate si_code to see if the segfault is ADI related.  */
+      si_code = parse_and_eval_long ("$_siginfo.si_code\n");
+
+      if (si_code >= SEGV_ACCADI && si_code <= SEGV_ADIPERR)
+        addr = parse_and_eval_long ("$_siginfo._sifields._sigfault.si_addr");
+    }
+  CATCH (exception, RETURN_MASK_ALL)
+    {
+      return;
+    }
+  END_CATCH
+
+  /* Print out ADI event based on sig_code value */
+  switch (si_code)
+    {
+    case SEGV_ACCADI:	/* adi not enabled */
+      printf_unfiltered (" (ADI disabled at address 0x%lx)\n", addr);
+      break;
+    case SEGV_ADIDERR:	/* disrupting mismatch */
+      printf_unfiltered (" (ADI deferred mismatch at address 0x%lx)\n", addr);
+      break;
+    case SEGV_ADIPERR:	/* precise mismatch */
+      printf_unfiltered (" (ADI precise mismatch at address 0x%lx)\n", addr);
+      break;
+    default:
+      break;
+    }
+}
+
 
 /* Return the address of a system call's alternative return
    address.  */
@@ -338,6 +385,8 @@  sparc64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
   set_xml_syscall_file_name (gdbarch, XML_SYSCALL_FILENAME_SPARC64);
   set_gdbarch_get_syscall_number (gdbarch,
                                   sparc64_linux_get_syscall_number);
+  set_gdbarch_handle_segmentation_fault (gdbarch,
+					 sparc64_linux_handle_segmentation_fault);
 }
 
 
diff --git a/gdb/sparc64-tdep.c b/gdb/sparc64-tdep.c
index 9e0e6b5..e8c5a63 100644
--- a/gdb/sparc64-tdep.c
+++ b/gdb/sparc64-tdep.c
@@ -165,7 +165,7 @@  sparc64_pstate_type (struct gdbarch *gdbarch)
       append_flags_type_flag (type, 8, "TLE");
       append_flags_type_flag (type, 9, "CLE");
       append_flags_type_flag (type, 10, "PID0");
-      append_flags_type_flag (type, 11, "PID1");
+      append_flags_type_flag (type, 11, "MCDE");
 
       tdep->sparc64_pstate_type = type;
     }
diff --git a/gdb/sparc64-tdep.h b/gdb/sparc64-tdep.h
index 324778e..d229c76 100644
--- a/gdb/sparc64-tdep.h
+++ b/gdb/sparc64-tdep.h
@@ -113,6 +113,8 @@  extern void sparc64_collect_fpregset (const struct sparc_fpregmap *fpregmap,
 				      const struct regcache *regcache,
 				      int regnum, void *fpregs);
 
+extern CORE_ADDR adi_normalize_address (CORE_ADDR addr);
+
 /* Functions and variables exported from sparc64-sol2-tdep.c.  */
 
 /* Register offsets for Solaris 2.  */