diff options
author | Nicholas Piggin <npiggin@gmail.com> | 2018-01-10 03:07:15 +1100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-02-16 20:09:35 +0100 |
commit | 973439da1137a066f6b3f478c930edff1879dee2 (patch) | |
tree | fe0e15b7ed8b8367bdc01bbd6388020ad554d08f /arch/powerpc | |
parent | 8dd311f1ec740b05c851d65bab9cfdde26e35a8a (diff) |
powerpc/64s: Convert slb_miss_common to use RFI_TO_USER/KERNEL
commit c7305645eb0c1621351cfc104038831ae87c0053 upstream.
In the SLB miss handler we may be returning to user or kernel. We need
to add a check early on and save the result in the cr4 register, and
then we bifurcate the return path based on that.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Backport to 4.4 based on patch from Balbir]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/powerpc')
-rw-r--r-- | arch/powerpc/kernel/exceptions-64s.S | 22 |
1 files changed, 20 insertions, 2 deletions
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index e3a3b81df363..2c6494351604 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -1503,6 +1503,8 @@ slb_miss_realmode: andi. r10,r12,MSR_RI /* check for unrecoverable exception */ beq- 2f + andi. r10,r12,MSR_PR /* check for user mode (PR != 0) */ + bne 1f .machine push .machine "power4" @@ -1516,7 +1518,23 @@ slb_miss_realmode: ld r11,PACA_EXSLB+EX_R11(r13) ld r12,PACA_EXSLB+EX_R12(r13) ld r13,PACA_EXSLB+EX_R13(r13) - rfid + RFI_TO_KERNEL + b . /* prevent speculative execution */ + +1: +.machine push +.machine "power4" + mtcrf 0x80,r9 + mtcrf 0x01,r9 /* slb_allocate uses cr0 and cr7 */ +.machine pop + + RESTORE_PPR_PACA(PACA_EXSLB, r9) + ld r9,PACA_EXSLB+EX_R9(r13) + ld r10,PACA_EXSLB+EX_R10(r13) + ld r11,PACA_EXSLB+EX_R11(r13) + ld r12,PACA_EXSLB+EX_R12(r13) + ld r13,PACA_EXSLB+EX_R13(r13) + RFI_TO_USER b . /* prevent speculative execution */ 2: mfspr r11,SPRN_SRR0 @@ -1525,7 +1543,7 @@ slb_miss_realmode: mtspr SPRN_SRR0,r10 ld r10,PACAKMSR(r13) mtspr SPRN_SRR1,r10 - rfid + RFI_TO_KERNEL b . unrecov_slb: |