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Martin KaFai Lau d5c47719f2 bpf: Adjust BPF_JMP that jumps to the 1st insn of the prologue
The next patch will add a ctx ptr saving instruction
"(r1 = *(u64 *)(r10 -8)" at the beginning for the main prog
when there is an epilogue patch (by the .gen_epilogue() verifier
ops added in the next patch).

There is one corner case if the bpf prog has a BPF_JMP that jumps
to the 1st instruction. It needs an adjustment such that
those BPF_JMP instructions won't jump to the newly added
ctx saving instruction.
The commit 5337ac4c9b ("bpf: Fix the corner case with may_goto and jump to the 1st insn.")
has the details on this case.

Note that the jump back to 1st instruction is not limited to the
ctx ptr saving instruction. The same also applies to the prologue.
A later test, pro_epilogue_goto_start.c, has a test for the prologue
only case.

Thus, this patch does one adjustment after gen_prologue and
the future ctx ptr saving. It is done by
adjust_jmp_off(env->prog, 0, delta) where delta has the total
number of instructions in the prologue and
the future ctx ptr saving instruction.

The adjust_jmp_off(env->prog, 0, delta) assumes that the
prologue does not have a goto 1st instruction itself.
To accommodate the prologue might have a goto 1st insn itself,
this patch changes the adjust_jmp_off() to skip considering
the instructions between [tgt_idx, tgt_idx + delta).

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240829210833.388152-3-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-29 18:15:44 -07:00
arch bpf, arm64: Avoid blindly saving/restoring all callee-saved registers 2024-08-28 08:41:33 -07:00
block block: Fix lockdep warning in blk_mq_mark_tag_wait 2024-08-15 19:25:03 -06:00
certs kbuild: use $(src) instead of $(srctree)/$(src) for source directory 2024-05-10 04:34:52 +09:00
crypto crypto: testmgr - generate power-of-2 lengths more often 2024-07-13 11:50:28 +12:00
Documentation docs/bpf: Fix a typo in verifier.rst 2024-08-29 12:19:30 -07:00
drivers platform-drivers-x86 for v6.11-4 2024-08-22 06:34:27 +08:00
fs Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2024-08-22 09:48:44 -07:00
include bpf: Move insn_buf[16] to bpf_verifier_env 2024-08-29 18:15:44 -07:00
init Rust fixes for v6.11 2024-08-16 11:24:06 -07:00
io_uring io_uring/sqpoll: annotate debug task == current with data_race() 2024-08-13 06:10:59 -06:00
ipc sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
kernel bpf: Adjust BPF_JMP that jumps to the 1st insn of the prologue 2024-08-29 18:15:44 -07:00
lib bcachefs fixes for 6.11-rc4 2024-08-17 09:46:10 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm 16 hotfixes. All except one are for MM. 10 of these are cc:stable and 2024-08-17 19:50:16 -07:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2024-08-22 09:48:44 -07:00
rust Rust fixes for v6.11 2024-08-16 11:24:06 -07:00
samples samples/bpf: tracex4: Fix failed to create kretprobe 'kmem_cache_alloc_node+0x0' 2024-08-27 16:17:44 -07:00
scripts Rust fixes for v6.11 2024-08-16 11:24:06 -07:00
security KEYS: trusted: dcp: fix leak of blob encryption key 2024-08-15 22:01:14 +03:00
sound ALSA: hda/tas2781: Use correct endian conversion 2024-08-14 16:58:26 +02:00
tools selftests/bpf: Make sure stashed kptr in local kptr is freed recursively 2024-08-29 12:18:26 -07:00
usr initramfs: shorten cmd_initfs in usr/Makefile 2024-07-16 01:07:52 +09:00
virt KVM: x86: Disallow read-only memslots for SEV-ES and SEV-SNP (and TDX) 2024-08-14 12:28:24 -04:00
.clang-format Docs: Move clang-format from process/ to dev-tools/ 2024-06-26 16:36:00 -06:00
.cocciconfig
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore Add Jeff Kirsher to .get_maintainer.ignore 2024-03-08 11:36:54 +00:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: add script and target to generate pacman package 2024-07-22 01:24:22 +09:00
.mailmap mailmap: update entry for David Heidelberg 2024-08-07 18:33:56 -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 tracing: Update of MAINTAINERS and CREDITS file 2024-07-18 14:08:42 -07:00
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 sound fixes for 6.11-rc3 2024-08-09 09:25:30 -07:00
Makefile Linux 6.11-rc4 2024-08-18 13:17:27 -07:00
README README: Fix spelling 2024-03-18 03:36:32 -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 reStructuredText 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.