4.14-stable patches

added patches:
	bpf-arm64-remove-prefetch-insn-in-xadd-mapping.patch

diff --git a/queue-4.14/bpf-arm64-remove-prefetch-insn-in-xadd-mapping.patch b/queue-4.14/bpf-arm64-remove-prefetch-insn-in-xadd-mapping.patch
new file mode 100644 (file)
index 0000000..6ad4b8d
--- /dev/null
+++ b/queue-4.14/bpf-arm64-remove-prefetch-insn-in-xadd-mapping.patch
@@ -0,0 +1,53 @@
+From 8968c67a82ab7501bc3b9439c3624a49b42fe54c Mon Sep 17 00:00:00 2001
+From: Daniel Borkmann <daniel@iogearbox.net>
+Date: Fri, 26 Apr 2019 21:48:21 +0200
+Subject: bpf, arm64: remove prefetch insn in xadd mapping
+
+From: Daniel Borkmann <daniel@iogearbox.net>
+
+commit 8968c67a82ab7501bc3b9439c3624a49b42fe54c upstream.
+
+Prefetch-with-intent-to-write is currently part of the XADD mapping in
+the AArch64 JIT and follows the kernel's implementation of atomic_add.
+This may interfere with other threads executing the LDXR/STXR loop,
+leading to potential starvation and fairness issues. Drop the optional
+prefetch instruction.
+
+Fixes: 85f68fe89832 ("bpf, arm64: implement jiting of BPF_XADD")
+Reported-by: Will Deacon <will.deacon@arm.com>
+Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
+Acked-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
+Acked-by: Will Deacon <will.deacon@arm.com>
+Signed-off-by: Alexei Starovoitov <ast@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ arch/arm64/net/bpf_jit.h      |    6 ------
+ arch/arm64/net/bpf_jit_comp.c |    1 -
+ 2 files changed, 7 deletions(-)
+
+--- a/arch/arm64/net/bpf_jit.h
++++ b/arch/arm64/net/bpf_jit.h
+@@ -100,12 +100,6 @@
+ #define A64_STXR(sf, Rt, Rn, Rs) \
+       A64_LSX(sf, Rt, Rn, Rs, STORE_EX)
+ 
+-/* Prefetch */
+-#define A64_PRFM(Rn, type, target, policy) \
+-      aarch64_insn_gen_prefetch(Rn, AARCH64_INSN_PRFM_TYPE_##type, \
+-                                AARCH64_INSN_PRFM_TARGET_##target, \
+-                                AARCH64_INSN_PRFM_POLICY_##policy)
+-
+ /* Add/subtract (immediate) */
+ #define A64_ADDSUB_IMM(sf, Rd, Rn, imm12, type) \
+       aarch64_insn_gen_add_sub_imm(Rd, Rn, imm12, \
+--- a/arch/arm64/net/bpf_jit_comp.c
++++ b/arch/arm64/net/bpf_jit_comp.c
+@@ -712,7 +712,6 @@ emit_cond_jmp:
+       case BPF_STX | BPF_XADD | BPF_DW:
+               emit_a64_mov_i(1, tmp, off, ctx);
+               emit(A64_ADD(1, tmp, tmp, dst), ctx);
+-              emit(A64_PRFM(tmp, PST, L1, STRM), ctx);
+               emit(A64_LDXR(isdw, tmp2, tmp), ctx);
+               emit(A64_ADD(isdw, tmp2, tmp2, src), ctx);
+               emit(A64_STXR(isdw, tmp2, tmp, tmp3), ctx);

diff --git a/queue-4.14/series b/queue-4.14/series
index f961062ee538225107c114d5943510336a06de79..d8cf46f2c807d95361529ad47bf11f034d5938fe 100644 (file)
--- a/queue-4.14/series
+++ b/queue-4.14/series
@@ -28,3 +28,4 @@ alsa-hda-hdmi-consider-eld_valid-when-reporting-jack-event.patch
 alsa-hda-realtek-eapd-turn-on-later.patch
 asoc-max98090-fix-restore-of-dapm-muxes.patch
 asoc-rt5677-spi-disable-16bit-spi-transfers.patch
+bpf-arm64-remove-prefetch-insn-in-xadd-mapping.patch