From: Mark Wielaard <mark@klomp.org>
Date: Tue, 19 Jun 2018 16:00:45 +0000 (+0200)
Subject: Mask AT_HWCAPS on arm64 to those instructions VEX implements.
X-Git-Tag: VALGRIND_3_14_0~96
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=fbbb696c5d1e93d4ac6cb548c68bb3f443ceef42;p=thirdparty%2Fvalgrind.git

Mask AT_HWCAPS on arm64 to those instructions VEX implements.

This patch makes sure that the process running under valgrind only sees
the AES, PMULL, SHA1, SHA2, CRC32, FP, and ASIMD features in auxv AT_HWCAPS.

https://bugs.kde.org/show_bug.cgi?id=381556
---

diff --git a/NEWS b/NEWS
index 004497199c..4fe7522bb4 100644
--- a/NEWS
+++ b/NEWS
@@ -71,6 +71,7 @@ where XXXXXX is the bug number as listed below.
 381289  epoll_pwait can have a NULL sigmask
 381274  powerpc too chatty even with --sigill-diagnostics=no
 381553  VEX register allocator v3
+381556  arm64: Handle feature registers access on 4.11 Linux kernel or later
 381769  Use ucontext_t instead of struct ucontext
 381805  arm32 needs ld.so index hardwire for new glibc security fixes
 382256  gz compiler flag test doesn't work for gold
diff --git a/coregrind/m_initimg/initimg-linux.c b/coregrind/m_initimg/initimg-linux.c
index 14b48dca85..61cc458bcf 100644
--- a/coregrind/m_initimg/initimg-linux.c
+++ b/coregrind/m_initimg/initimg-linux.c
@@ -705,9 +705,16 @@ Addr setup_client_stack( void*  init_sp,
             }
 #           elif defined(VGP_arm64_linux)
             {
-               /* Linux 4.11 started pupulating this for arm64, but we
-                  currently don't support any. Bug KDE#381556. */
-               auxv->u.a_val = 0;
+               /* Limit the AT_HWCAP to just those features we explicitly
+		  support in VEX.  */
+#define ARM64_SUPPORTED_HWCAP (VKI_HWCAP_AES	        \
+                               | VKI_HWCAP_PMULL        \
+                               | VKI_HWCAP_SHA1         \
+                               | VKI_HWCAP_SHA2         \
+                               | VKI_HWCAP_CRC32        \
+                               | VKI_HWCAP_FP           \
+                               | VKI_HWCAP_ASIMD)
+               auxv->u.a_val &= ARM64_SUPPORTED_HWCAP;
             }
 #           endif
             break;
diff --git a/include/vki/vki-arm64-linux.h b/include/vki/vki-arm64-linux.h
index af6b435724..54b0428d93 100644
--- a/include/vki/vki-arm64-linux.h
+++ b/include/vki/vki-arm64-linux.h
@@ -691,6 +691,39 @@ struct vki_shminfo64 {
 #define VKI_TIOCGSERIAL     0x541E
 #define VKI_TIOCSSERIAL     0x541F
 
+//----------------------------------------------------------------------
+// From linux-4.17/include/uapi/asm-generic/ioctls.h
+//----------------------------------------------------------------------
+
+#define VKI_HWCAP_FP                (1 << 0)
+#define VKI_HWCAP_ASIMD             (1 << 1)
+#define VKI_HWCAP_EVTSTRM           (1 << 2)
+#define VKI_HWCAP_AES               (1 << 3)
+#define VKI_HWCAP_PMULL             (1 << 4)
+#define VKI_HWCAP_SHA1              (1 << 5)
+#define VKI_HWCAP_SHA2              (1 << 6)
+#define VKI_HWCAP_CRC32             (1 << 7)
+#define VKI_HWCAP_ATOMICS           (1 << 8)
+#define VKI_HWCAP_FPHP              (1 << 9)
+#define VKI_HWCAP_ASIMDHP           (1 << 10)
+#define VKI_HWCAP_CPUID             (1 << 11)
+#define VKI_HWCAP_ASIMDRDM          (1 << 12)
+#define VKI_HWCAP_JSCVT             (1 << 13)
+#define VKI_HWCAP_FCMA              (1 << 14)
+#define VKI_HWCAP_LRCPC             (1 << 15)
+#define VKI_HWCAP_DCPOP             (1 << 16)
+#define VKI_HWCAP_SHA3              (1 << 17)
+#define VKI_HWCAP_SM3               (1 << 18)
+#define VKI_HWCAP_SM4               (1 << 19)
+#define VKI_HWCAP_ASIMDDP           (1 << 20)
+#define VKI_HWCAP_SHA512            (1 << 21)
+#define VKI_HWCAP_SVE               (1 << 22)
+#define VKI_HWCAP_ASIMDFHM          (1 << 23)
+#define VKI_HWCAP_DIT               (1 << 24)
+#define VKI_HWCAP_USCAT             (1 << 25)
+#define VKI_HWCAP_ILRCPC            (1 << 26)
+#define VKI_HWCAP_FLAGM             (1 << 27)
+
 //----------------------------------------------------------------------
 // And that's it!
 //----------------------------------------------------------------------