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Thomas Richter 5069211e2f perf trace: Use the right bpf_probe_read(_str) variant for reading user data
Perf test case 111 Check open filename arg using perf trace + vfs_getname
fails on s390. This is caused by a failing function
bpf_probe_read() in file util/bpf_skel/augmented_raw_syscalls.bpf.c.

The root cause is the lookup by address. Function bpf_probe_read()
is used. This function works only for architectures
with ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE.

On s390 is not possible to determine from the address to which
address space the address belongs to (user or kernel space).

Replace bpf_probe_read() by bpf_probe_read_kernel()
and bpf_probe_read_str() by bpf_probe_read_user_str() to
explicity specify the address space the address refers to.

Output before:
 # ./perf trace -eopen,openat -- touch /tmp/111
 libbpf: prog 'sys_enter': BPF program load failed: Invalid argument
 libbpf: prog 'sys_enter': -- BEGIN PROG LOAD LOG --
 reg type unsupported for arg#0 function sys_enter#75
 0: R1=ctx(off=0,imm=0) R10=fp0
 ; int sys_enter(struct syscall_enter_args *args)
 0: (bf) r6 = r1           ; R1=ctx(off=0,imm=0) R6_w=ctx(off=0,imm=0)
 ; return bpf_get_current_pid_tgid();
 1: (85) call bpf_get_current_pid_tgid#14      ; R0_w=scalar()
 2: (63) *(u32 *)(r10 -8) = r0 ; R0_w=scalar() R10=fp0 fp-8=????mmmm
 3: (bf) r2 = r10              ; R2_w=fp0 R10=fp0
 ;
 .....
 lines deleted here
 .....
 23: (bf) r3 = r6              ; R3_w=ctx(off=0,imm=0) R6=ctx(off=0,imm=0)
 24: (85) call bpf_probe_read#4
 unknown func bpf_probe_read#4
 processed 23 insns (limit 1000000) max_states_per_insn 0 \
	 total_states 2 peak_states 2 mark_read 2
 -- END PROG LOAD LOG --
 libbpf: prog 'sys_enter': failed to load: -22
 libbpf: failed to load object 'augmented_raw_syscalls_bpf'
 libbpf: failed to load BPF skeleton 'augmented_raw_syscalls_bpf': -22
 ....

Output after:
 # ./perf test -Fv 111
 111: Check open filename arg using perf trace + vfs_getname          :
 --- start ---
     1.085 ( 0.011 ms): touch/320753 openat(dfd: CWD, filename: \
	"/tmp/temporary_file.SWH85", \
	flags: CREAT|NOCTTY|NONBLOCK|WRONLY, mode: IRUGO|IWUGO) = 3
 ---- end ----
 Check open filename arg using perf trace + vfs_getname: Ok
 #

Test with the sleep command shows:
Output before:
 # ./perf trace -e *sleep sleep 1.234567890
     0.000 (1234.681 ms): sleep/63114 clock_nanosleep(rqtp: \
         { .tv_sec: 0, .tv_nsec: 0 }, rmtp: 0x3ffe0979720) = 0
 #

Output after:
 # ./perf trace -e *sleep sleep 1.234567890
     0.000 (1234.686 ms): sleep/64277 clock_nanosleep(rqtp: \
         { .tv_sec: 1, .tv_nsec: 234567890 }, rmtp: 0x3fff3df9ea0) = 0
 #

Fixes: 14e4b9f428 ("perf trace: Raw augmented syscalls fix libbpf 1.0+ compatibility")
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Co-developed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ian Rogers <irogers@google.com>
Cc: gor@linux.ibm.com
Cc: hca@linux.ibm.com
Cc: sumanthk@linux.ibm.com
Cc: svens@linux.ibm.com
Link: https://lore.kernel.org/r/20231019082642.3286650-1-tmricht@linux.ibm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2023-10-19 22:41:46 -07:00
arch Fix preemption delays in the SGX code, remove unnecessarily UAPI-exported code, 2023-09-10 10:39:31 -07:00
block block: fix pin count management when merging same-page segments 2023-09-06 07:32:27 -06:00
certs certs: Reference revocation list for all keyrings 2023-08-17 20:12:41 +00:00
crypto This update includes the following changes: 2023-08-29 11:23:29 -07:00
Documentation drm ci for 6.6-rc1 2023-09-10 11:55:26 -07:00
drivers drm ci for 6.6-rc1 2023-09-10 11:55:26 -07:00
fs six smb3 client fixes, one fix for nls Kconfig, one minor spnego registry update 2023-09-09 19:56:23 -07:00
include six smb3 client fixes, one fix for nls Kconfig, one minor spnego registry update 2023-09-09 19:56:23 -07:00
init workqueue: Changes for v6.6 2023-09-01 16:06:32 -07:00
io_uring Revert "io_uring: fix IO hang in io_wq_put_and_exit from do_exit()" 2023-09-07 09:41:49 -06:00
ipc Add x86 shadow stack support 2023-08-31 12:20:12 -07:00
kernel RISC-V Patches for the 6.6 Merge Window, Part 2 (try 2) 2023-09-09 14:25:11 -07:00
lib iov_iter: Kunit tests for page extraction 2023-09-09 15:11:49 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm LoongArch changes for v6.6 2023-09-08 12:16:52 -07:00
net Including fixes from netfilter and bpf. 2023-09-07 18:33:07 -07:00
rust Documentation work keeps chugging along; stuff for 6.6 includes: 2023-08-30 20:05:42 -07:00
samples VFIO updates for v6.6-rc1 2023-08-30 20:36:01 -07:00
scripts run-clang-tools: Add pass through checks and and header-filter arguments 2023-10-12 10:01:55 -07:00
security Landlock updates for v6.6-rc1 2023-09-08 12:06:51 -07:00
sound sound fixes for 6.6-rc1 2023-09-08 13:07:50 -07:00
tools perf trace: Use the right bpf_probe_read(_str) variant for reading user data 2023-10-19 22:41:46 -07:00
usr initramfs: Encode dependency on KBUILD_BUILD_TIMESTAMP 2023-06-06 17:54:49 +09:00
virt ARM: 2023-09-07 13:52:20 -07:00
.clang-format iommu: Add for_each_group_device() 2023-05-23 08:15:51 +02:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: rpm-pkg: rename binkernel.spec to kernel.spec 2023-07-25 00:59:33 +09:00
.mailmap for-linus-2023083101 2023-09-01 12:31:44 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS USB: Remove Wireless USB and UWB documentation 2023-08-09 14:17:32 +02:00
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 drm ci for 6.6-rc1 2023-09-10 11:55:26 -07:00
Makefile Linux 6.6-rc1 2023-09-10 16:28:41 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.