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Alexander Duyck 7a4c79329b bpf, arm64: Fix BTI type used for freplace attached functions
[ Upstream commit a3f25d614b ]

When running an freplace attached bpf program on an arm64 system w were
seeing the following issue:
  Unhandled 64-bit el1h sync exception on CPU47, ESR 0x0000000036000003 -- BTI

After a bit of work to track it down I determined that what appeared to be
happening is that the 'bti c' at the start of the program was somehow being
reached after a 'br' instruction. Further digging pointed me toward the
fact that the function was attached via freplace. This in turn led me to
build_plt which I believe is invoking the long jump which is triggering
this error.

To resolve it we can replace the 'bti c' with 'bti jc' and add a comment
explaining why this has to be modified as such.

Fixes: b2ad54e153 ("bpf, arm64: Implement bpf_arch_text_poke() for arm64")
Signed-off-by: Alexander Duyck <alexanderduyck@fb.com>
Acked-by: Xu Kuohai <xukuohai@huawei.com>
Link: https://lore.kernel.org/r/168926677665.316237.9953845318337455525.stgit@ahduyck-xeon-server.home.arpa
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-27 08:57:00 +02:00
Documentation media: uapi: Fix [GS]_ROUTING ACTIVE flag value 2023-07-23 13:54:08 +02:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
arch bpf, arm64: Fix BTI type used for freplace attached functions 2023-07-27 08:57:00 +02:00
block blk-mq: fix NULL dereference on q->elevator in blk_mq_elv_switch_none 2023-07-27 08:56:45 +02:00
certs KEYS: Add missing function documentation 2023-04-24 16:15:52 +03:00
crypto crypto: jitter - correct health test during initialization 2023-07-19 16:36:19 +02:00
drivers octeontx2-pf: Dont allocate BPIDs for LBK interfaces 2023-07-27 08:56:59 +02:00
fs cifs: fix mid leak during reconnection after timeout threshold 2023-07-27 08:56:56 +02:00
include sched/psi: use kernfs polling functions for PSI trigger polling 2023-07-27 08:56:53 +02:00
init kbuild: Fix CFI failures with GCOV 2023-07-19 16:36:23 +02:00
io_uring io_uring: Fix io_uring mmap() by using architecture-provided get_unmapped_area() 2023-07-27 08:56:31 +02:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel bpf: Repeat check_max_stack_depth for async callbacks 2023-07-27 08:56:59 +02:00
lib iov_iter: Mark copy_iovec_from_user() noclone 2023-07-27 08:56:53 +02:00
mm mm/mlock: fix vma iterator conversion of apply_vma_lock_flags() 2023-07-27 08:56:32 +02:00
net net: sched: cls_bpf: Undo tcf_bind_filter in case of an error 2023-07-27 08:56:57 +02:00
rust Rust changes for v6.4 2023-04-30 11:20:22 -07:00
samples samples: ftrace: Save required argument registers in sample trampolines 2023-07-23 13:54:09 +02:00
scripts kallsyms: strip LTO-only suffixes from promoted global functions 2023-07-27 08:56:54 +02:00
security security: keys: Modify mismatched function name 2023-07-27 08:56:59 +02:00
sound ASoC: SOF: ipc3-dtrace: uninitialized data in dfsentry_trace_filter_write() 2023-07-27 08:56:56 +02:00
tools perf build: Fix library not found error when using CSLIBS 2023-07-27 08:56:54 +02:00
usr initramfs: Check negative timestamp to prevent broken cpio archive 2023-04-16 17:37:01 +09:00
virt KVM: Avoid illegal stage2 mapping on invalid memory slot 2023-06-22 15:14:57 -04:00
.clang-format cxl for v6.4 2023-04-30 11:51:51 -07:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for *.dtso files 2023-02-26 15:28:23 +09:00
.gitignore linux-kselftest-kunit-6.4-rc1 2023-04-24 12:31:32 -07:00
.mailmap mailmap: add entries for Ben Dooks 2023-06-19 13:19:35 -07:00
.rustfmt.toml rust: add `.rustfmt.toml` 2022-09-28 09:02:20 +02:00
COPYING
CREDITS MAINTAINERS: sctp: move Neil to CREDITS 2023-05-12 08:51:32 +01:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Networking fixes for 6.4-rc8, including fixes from ipsec, bpf, 2023-06-22 17:59:51 -07:00
Makefile Linux 6.4.6 2023-07-24 18:56:41 +02:00
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