qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Richard Henderson <richard.henderson@linaro.org>
To: qemu-devel@nongnu.org
Cc: qemu-arm@nongnu.org, Peter Maydell <peter.maydell@linaro.org>
Subject: [PATCH v3 11/14] target/arm: Implement gdbstub pauth extension
Date: Mon, 27 Feb 2023 11:33:26 -1000	[thread overview]
Message-ID: <20230227213329.793795-12-richard.henderson@linaro.org> (raw)
In-Reply-To: <20230227213329.793795-1-richard.henderson@linaro.org>

The extension is primarily defined by the Linux kernel NT_ARM_PAC_MASK
ptrace register set.

The original gdb feature consists of two masks, data and code, which are
used to mask out the authentication code within a pointer.  Following
discussion with Luis Machado, add two more masks in order to support
pointers within the high half of the address space (i.e. TTBR1 vs TTBR0).

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1105
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 configs/targets/aarch64-linux-user.mak    |  2 +-
 configs/targets/aarch64-softmmu.mak       |  2 +-
 configs/targets/aarch64_be-linux-user.mak |  2 +-
 target/arm/internals.h                    |  2 ++
 target/arm/gdbstub.c                      |  5 ++++
 target/arm/gdbstub64.c                    | 34 +++++++++++++++++++++++
 gdb-xml/aarch64-pauth.xml                 | 15 ++++++++++
 7 files changed, 59 insertions(+), 3 deletions(-)
 create mode 100644 gdb-xml/aarch64-pauth.xml

diff --git a/configs/targets/aarch64-linux-user.mak b/configs/targets/aarch64-linux-user.mak
index db552f1839..ba8bc5fe3f 100644
--- a/configs/targets/aarch64-linux-user.mak
+++ b/configs/targets/aarch64-linux-user.mak
@@ -1,6 +1,6 @@
 TARGET_ARCH=aarch64
 TARGET_BASE_ARCH=arm
-TARGET_XML_FILES= gdb-xml/aarch64-core.xml gdb-xml/aarch64-fpu.xml
+TARGET_XML_FILES= gdb-xml/aarch64-core.xml gdb-xml/aarch64-fpu.xml gdb-xml/aarch64-pauth.xml
 TARGET_HAS_BFLT=y
 CONFIG_SEMIHOSTING=y
 CONFIG_ARM_COMPATIBLE_SEMIHOSTING=y
diff --git a/configs/targets/aarch64-softmmu.mak b/configs/targets/aarch64-softmmu.mak
index d489e6da83..b4338e9568 100644
--- a/configs/targets/aarch64-softmmu.mak
+++ b/configs/targets/aarch64-softmmu.mak
@@ -1,5 +1,5 @@
 TARGET_ARCH=aarch64
 TARGET_BASE_ARCH=arm
 TARGET_SUPPORTS_MTTCG=y
-TARGET_XML_FILES= gdb-xml/aarch64-core.xml gdb-xml/aarch64-fpu.xml gdb-xml/arm-core.xml gdb-xml/arm-vfp.xml gdb-xml/arm-vfp3.xml gdb-xml/arm-vfp-sysregs.xml gdb-xml/arm-neon.xml gdb-xml/arm-m-profile.xml gdb-xml/arm-m-profile-mve.xml
+TARGET_XML_FILES= gdb-xml/aarch64-core.xml gdb-xml/aarch64-fpu.xml gdb-xml/arm-core.xml gdb-xml/arm-vfp.xml gdb-xml/arm-vfp3.xml gdb-xml/arm-vfp-sysregs.xml gdb-xml/arm-neon.xml gdb-xml/arm-m-profile.xml gdb-xml/arm-m-profile-mve.xml gdb-xml/aarch64-pauth.xml
 TARGET_NEED_FDT=y
diff --git a/configs/targets/aarch64_be-linux-user.mak b/configs/targets/aarch64_be-linux-user.mak
index dc78044fb1..acb5620cdb 100644
--- a/configs/targets/aarch64_be-linux-user.mak
+++ b/configs/targets/aarch64_be-linux-user.mak
@@ -1,7 +1,7 @@
 TARGET_ARCH=aarch64
 TARGET_BASE_ARCH=arm
 TARGET_BIG_ENDIAN=y
-TARGET_XML_FILES= gdb-xml/aarch64-core.xml gdb-xml/aarch64-fpu.xml
+TARGET_XML_FILES= gdb-xml/aarch64-core.xml gdb-xml/aarch64-fpu.xml gdb-xml/aarch64-pauth.xml
 TARGET_HAS_BFLT=y
 CONFIG_SEMIHOSTING=y
 CONFIG_ARM_COMPATIBLE_SEMIHOSTING=y
diff --git a/target/arm/internals.h b/target/arm/internals.h
index c02dd59743..97271117a4 100644
--- a/target/arm/internals.h
+++ b/target/arm/internals.h
@@ -1347,6 +1347,8 @@ int aarch64_gdb_get_sve_reg(CPUARMState *env, GByteArray *buf, int reg);
 int aarch64_gdb_set_sve_reg(CPUARMState *env, uint8_t *buf, int reg);
 int aarch64_gdb_get_fpu_reg(CPUARMState *env, GByteArray *buf, int reg);
 int aarch64_gdb_set_fpu_reg(CPUARMState *env, uint8_t *buf, int reg);
+int aarch64_gdb_get_pauth_reg(CPUARMState *env, GByteArray *buf, int reg);
+int aarch64_gdb_set_pauth_reg(CPUARMState *env, uint8_t *buf, int reg);
 void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp);
 void arm_cpu_sme_finalize(ARMCPU *cpu, Error **errp);
 void arm_cpu_pauth_finalize(ARMCPU *cpu, Error **errp);
diff --git a/target/arm/gdbstub.c b/target/arm/gdbstub.c
index bf8aff7824..062c8d447a 100644
--- a/target/arm/gdbstub.c
+++ b/target/arm/gdbstub.c
@@ -355,6 +355,11 @@ void arm_cpu_register_gdb_regs_for_features(ARMCPU *cpu)
                                      aarch64_gdb_set_fpu_reg,
                                      34, "aarch64-fpu.xml", 0);
         }
+        if (isar_feature_aa64_pauth(&cpu->isar)) {
+            gdb_register_coprocessor(cs, aarch64_gdb_get_pauth_reg,
+                                     aarch64_gdb_set_pauth_reg,
+                                     4, "aarch64-pauth.xml", 0);
+        }
 #endif
     } else {
         if (arm_feature(env, ARM_FEATURE_NEON)) {
diff --git a/target/arm/gdbstub64.c b/target/arm/gdbstub64.c
index 3d9e9e97c8..3bee892fb7 100644
--- a/target/arm/gdbstub64.c
+++ b/target/arm/gdbstub64.c
@@ -210,6 +210,40 @@ int aarch64_gdb_set_sve_reg(CPUARMState *env, uint8_t *buf, int reg)
     return 0;
 }
 
+int aarch64_gdb_get_pauth_reg(CPUARMState *env, GByteArray *buf, int reg)
+{
+    switch (reg) {
+    case 0: /* pauth_dmask */
+    case 1: /* pauth_cmask */
+    case 2: /* pauth_dmask_high */
+    case 3: /* pauth_cmask_high */
+        /*
+         * Note that older versions of this feature only contained
+         * pauth_{d,c}mask, for use with Linux user processes, and
+         * thus exclusively in the low half of the address space.
+         *
+         * To support system mode, and to debug kernels, two new regs
+         * were added to cover the high half of the address space.
+         * For the purpose of pauth_ptr_mask, we can use any well-formed
+         * address within the address space half -- here, 0 and -1.
+         */
+        {
+            bool is_data = !(reg & 1);
+            bool is_high = reg & 2;
+            uint64_t mask = pauth_ptr_mask(env, -is_high, is_data);
+            return gdb_get_reg64(buf, mask);
+        }
+    default:
+        return 0;
+    }
+}
+
+int aarch64_gdb_set_pauth_reg(CPUARMState *env, uint8_t *buf, int reg)
+{
+    /* All pseudo registers are read-only. */
+    return 0;
+}
+
 static void output_vector_union_type(GString *s, int reg_width,
                                      const char *name)
 {
diff --git a/gdb-xml/aarch64-pauth.xml b/gdb-xml/aarch64-pauth.xml
new file mode 100644
index 0000000000..24af5f903c
--- /dev/null
+++ b/gdb-xml/aarch64-pauth.xml
@@ -0,0 +1,15 @@
+<?xml version="1.0"?>
+<!-- Copyright (C) 2018-2022 Free Software Foundation, Inc.
+
+     Copying and distribution of this file, with or without modification,
+     are permitted in any medium without royalty provided the copyright
+     notice and this notice are preserved.  -->
+
+<!DOCTYPE feature SYSTEM "gdb-target.dtd">
+<feature name="org.gnu.gdb.aarch64.pauth">
+  <reg name="pauth_dmask" bitsize="64"/>
+  <reg name="pauth_cmask" bitsize="64"/>
+  <reg name="pauth_dmask_high" bitsize="64"/>
+  <reg name="pauth_cmask_high" bitsize="64"/>
+</feature>
+
-- 
2.34.1



  parent reply	other threads:[~2023-02-27 21:36 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-02-27 21:33 [PATCH v3 00/14] target/arm: gdbstub cleanups and additions Richard Henderson
2023-02-27 21:33 ` [PATCH v3 01/14] target/arm: Normalize aarch64 gdbstub get/set function names Richard Henderson
2023-02-27 21:33 ` [PATCH v3 02/14] target/arm: Unexport arm_gen_dynamic_sysreg_xml Richard Henderson
2023-02-27 21:33 ` [PATCH v3 03/14] target/arm: Move arm_gen_dynamic_svereg_xml to gdbstub64.c Richard Henderson
2023-02-27 21:33 ` [PATCH v3 04/14] target/arm: Split out output_vector_union_type Richard Henderson
2023-02-27 21:33 ` [PATCH v3 05/14] target/arm: Simplify register counting in arm_gen_dynamic_svereg_xml Richard Henderson
2023-02-27 21:33 ` [PATCH v3 06/14] target/arm: Hoist pred_width " Richard Henderson
2023-02-27 21:33 ` [PATCH v3 07/14] target/arm: Fix svep width " Richard Henderson
2023-02-27 21:33 ` [PATCH v3 08/14] target/arm: Add name argument to output_vector_union_type Richard Henderson
2023-02-27 21:33 ` [PATCH v3 09/14] target/arm: Simplify iteration over bit widths Richard Henderson
2023-02-27 21:33 ` [PATCH v3 10/14] target/arm: Create pauth_ptr_mask Richard Henderson
2023-02-27 21:33 ` Richard Henderson [this message]
2023-02-27 21:33 ` [PATCH v3 12/14] target/arm: Export arm_v7m_mrs_control Richard Henderson
2023-02-27 21:33 ` [PATCH v3 13/14] target/arm: Export arm_v7m_get_sp_ptr Richard Henderson
2023-02-27 21:33 ` [PATCH v3 14/14] target/arm: Implement gdbstub m-profile systemreg and secext Richard Henderson
2023-03-03 14:03 ` [PATCH v3 00/14] target/arm: gdbstub cleanups and additions Peter Maydell

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20230227213329.793795-12-richard.henderson@linaro.org \
    --to=richard.henderson@linaro.org \
    --cc=peter.maydell@linaro.org \
    --cc=qemu-arm@nongnu.org \
    --cc=qemu-devel@nongnu.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).