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From: Michael Ellerman <mpe@ellerman.id.au>
To: Alexander.Levin@microsoft.com
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org, npiggin@gmail.com
Subject: [PATCH v4.1 backport 04/15] powerpc/64: Convert fast_exception_return to use RFI_TO_USER/KERNEL
Date: Fri,  2 Mar 2018 15:45:38 +1100	[thread overview]
Message-ID: <20180302044549.14930-5-mpe@ellerman.id.au> (raw)
In-Reply-To: <20180302044549.14930-1-mpe@ellerman.id.au>

From: Nicholas Piggin <npiggin@gmail.com>

commit a08f828cf47e6c605af21d2cdec68f84e799c318 upstream.

Similar to the syscall return path, in fast_exception_return we may be
returning to user or kernel context. We already have a test for that,
because we conditionally restore r13. So use that existing test and
branch, and bifurcate the return based on that.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/kernel/entry_64.S | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index e3bb07c78cee..f7421248cbd8 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -845,7 +845,7 @@ BEGIN_FTR_SECTION
 END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 	ACCOUNT_CPU_USER_EXIT(r2, r4)
 	REST_GPR(13, r1)
-1:
+
 	mtspr	SPRN_SRR1,r3
 
 	ld	r2,_CCR(r1)
@@ -858,8 +858,22 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 	ld	r3,GPR3(r1)
 	ld	r4,GPR4(r1)
 	ld	r1,GPR1(r1)
+	RFI_TO_USER
+	b	.	/* prevent speculative execution */
+
+1:	mtspr	SPRN_SRR1,r3
 
-	rfid
+	ld	r2,_CCR(r1)
+	mtcrf	0xFF,r2
+	ld	r2,_NIP(r1)
+	mtspr	SPRN_SRR0,r2
+
+	ld	r0,GPR0(r1)
+	ld	r2,GPR2(r1)
+	ld	r3,GPR3(r1)
+	ld	r4,GPR4(r1)
+	ld	r1,GPR1(r1)
+	RFI_TO_KERNEL
 	b	.	/* prevent speculative execution */
 
 #endif /* CONFIG_PPC_BOOK3E */
-- 
2.14.1

  parent reply	other threads:[~2018-03-02  4:45 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-03-02  4:45 [PATCH v4.1 backport 00/15] powerpc stable backports for v4.1 Michael Ellerman
2018-03-02  4:45 ` [PATCH v4.1 backport 01/15] powerpc/pseries: Add H_GET_CPU_CHARACTERISTICS flags & wrapper Michael Ellerman
2018-03-02  4:45 ` [PATCH v4.1 backport 02/15] powerpc/64: Add macros for annotating the destination of rfid/hrfid Michael Ellerman
2018-03-02  4:45 ` [PATCH v4.1 backport 03/15] powerpc/64s: Simple RFI macro conversions Michael Ellerman
2018-03-02  4:45 ` Michael Ellerman [this message]
2018-03-02  4:45 ` [PATCH v4.1 backport 05/15] powerpc/64: Convert the syscall exit path to use RFI_TO_USER/KERNEL Michael Ellerman
2018-03-02  4:45 ` [PATCH v4.1 backport 06/15] powerpc/64s: Convert slb_miss_common " Michael Ellerman
2018-03-02  4:45 ` [PATCH v4.1 backport 07/15] powerpc/64s: Add support for RFI flush of L1-D cache Michael Ellerman
2018-03-02  4:45 ` [PATCH v4.1 backport 08/15] powerpc/64s: Support disabling RFI flush with no_rfi_flush and nopti Michael Ellerman
2018-03-02  4:45 ` [PATCH v4.1 backport 09/15] powerpc/64s: Improve RFI L1-D cache flush fallback Michael Ellerman
2018-03-02  4:45 ` [PATCH v4.1 backport 10/15] powerpc/pseries: Query hypervisor for RFI flush settings Michael Ellerman
2018-03-02  4:45 ` [PATCH v4.1 backport 11/15] powerpc/powernv: Check device-tree " Michael Ellerman
2018-03-02  4:45 ` [PATCH v4.1 backport 12/15] powerpc/64s: Allow control of RFI flush via debugfs Michael Ellerman
2018-03-02  4:45 ` [PATCH v4.1 backport 13/15] powerpc/pseries: include linux/types.h in asm/hvcall.h Michael Ellerman
2018-03-02  4:45 ` [PATCH v4.1 backport 14/15] powerpc/ptrace: Fix out of bounds array access warning Michael Ellerman
2018-03-02  4:45 ` [PATCH v4.1 backport 15/15] powerpc/vdso64: Use double word compare on pointers Michael Ellerman
2018-03-03 22:17 ` [PATCH v4.1 backport 00/15] powerpc stable backports for v4.1 Sasha Levin

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