linux-kernel - [PATCH stable 3.10, 3.12, 3.14] MIPS: Export FP functions used by lose

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 5 Mar 2015 16:08:44 +0000
From:	James Hogan <james.hogan@...tec.com>
To:	Guenter Roeck <linux@...ck-us.net>
CC:	<linux-kernel@...r.kernel.org>, <torvalds@...ux-foundation.org>,
	<akpm@...ux-foundation.org>, <satoru.takeuchi@...il.com>,
	<shuah.kh@...sung.com>, <stable@...r.kernel.org>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	<linux-mips@...ux-mips.org>, James Hogan <james.hogan@...tec.com>,
	Paolo Bonzini <pbonzini@...hat.com>,
	Ralf Baechle <ralf@...ux-mips.org>,
	Paul Burton <paul.burton@...tec.com>,
	Gleb Natapov <gleb@...nel.org>, <kvm@...r.kernel.org>
Subject: [PATCH stable 3.10, 3.12, 3.14] MIPS: Export FP functions used by lose_fpu(1) for KVM

[ Upstream commit 3ce465e04bfd8de9956d515d6e9587faac3375dc ]

Export the _save_fp asm function used by the lose_fpu(1) macro to GPL
modules so that KVM can make use of it when it is built as a module.

This fixes the following build error when CONFIG_KVM=m due to commit
f798217dfd03 ("KVM: MIPS: Don't leak FPU/DSP to guest"):

ERROR: "_save_fp" [arch/mips/kvm/kvm.ko] undefined!

Signed-off-by: James Hogan <james.hogan@...tec.com>
Fixes: f798217dfd03 (KVM: MIPS: Don't leak FPU/DSP to guest)
Cc: Paolo Bonzini <pbonzini@...hat.com>
Cc: Ralf Baechle <ralf@...ux-mips.org>
Cc: Paul Burton <paul.burton@...tec.com>
Cc: Gleb Natapov <gleb@...nel.org>
Cc: kvm@...r.kernel.org
Cc: linux-mips@...ux-mips.org
Cc: <stable@...r.kernel.org> # 3.10...3.15
Patchwork: https://patchwork.linux-mips.org/patch/9260/
Signed-off-by: Ralf Baechle <ralf@...ux-mips.org>
[james.hogan@...tec.com: Only export when CPU_R4K_FPU=y prior to v3.16,
 so as not to break the Octeon build which excludes FPU support. KVM
 depends on MIPS32r2 anyway.]
Signed-off-by: James Hogan <james.hogan@...tec.com>
---
Appologies for the previous cavium_octeon_defconfig link breakage.
Octeon has the symbol since 3.16, but not before. This backport should
do the trick for stable 3.10, 3.12, and 3.14. Build tested with
cavium_octeon_defconfig and malta_kvm_defconfig on those stable
branches.
---
 arch/mips/kernel/mips_ksyms.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/mips/kernel/mips_ksyms.c b/arch/mips/kernel/mips_ksyms.c
index 6e58e97fcd39..cedeb5686eb5 100644
--- a/arch/mips/kernel/mips_ksyms.c
+++ b/arch/mips/kernel/mips_ksyms.c
@@ -14,6 +14,7 @@
 #include <linux/mm.h>
 #include <asm/uaccess.h>
 #include <asm/ftrace.h>
+#include <asm/fpu.h>
 
 extern void *__bzero(void *__s, size_t __count);
 extern long __strncpy_from_user_nocheck_asm(char *__to,
@@ -26,6 +27,13 @@ extern long __strnlen_user_nocheck_asm(const char *s);
 extern long __strnlen_user_asm(const char *s);
 
 /*
+ * Core architecture code
+ */
+#ifdef CONFIG_CPU_R4K_FPU
+EXPORT_SYMBOL_GPL(_save_fp);
+#endif
+
+/*
  * String functions
  */
 EXPORT_SYMBOL(memset);
-- 
2.0.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/