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Linus Torvalds 291073a566 kvm: fix objtool relocation warning
The recent change to make objtool aware of more symbol relocation types
(commit 24ff652573: "objtool: Teach get_alt_entry() about more
relocation types") also added another check, and resulted in this
objtool warning when building kvm on x86:

    arch/x86/kvm/emulate.o: warning: objtool: __ex_table+0x4: don't know how to handle reloc symbol type: kvm_fastop_exception

The reason seems to be that kvm_fastop_exception() is marked as a global
symbol, which causes the relocation to ke kept around for objtool.  And
at the same time, the kvm_fastop_exception definition (which is done as
an inline asm statement) doesn't actually set the type of the global,
which then makes objtool unhappy.

The minimal fix is to just not mark kvm_fastop_exception as being a
global symbol.  It's only used in that one compilation unit anyway, so
it was always pointless.  That's how all the other local exception table
labels are done.

I'm not entirely happy about the kinds of games that the kvm code plays
with doing its own exception handling, and the fact that it confused
objtool is most definitely a symptom of the code being a bit too subtle
and ad-hoc.  But at least this trivial one-liner makes objtool no longer
upset about what is going on.

Fixes: 24ff652573 ("objtool: Teach get_alt_entry() about more relocation types")
Link: https://lore.kernel.org/lkml/CAHk-=wiZwq-0LknKhXN4M+T8jbxn_2i9mcKpO+OaBSSq_Eh7tg@mail.gmail.com/
Cc: Borislav Petkov <bp@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-10-03 13:34:19 -07:00
arch kvm: fix objtool relocation warning 2021-10-03 13:34:19 -07:00
block block-5.15-2021-10-01 2021-10-02 11:00:36 -07:00
certs certs: Add support for using elliptic curve keys for signing modules 2021-08-23 19:55:42 +03:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2021-08-30 12:57:10 -07:00
Documentation Char/Misc driver fixes for 5.15-rc4 2021-10-03 11:19:02 -07:00
drivers Char/Misc driver fixes for 5.15-rc4 2021-10-03 11:19:02 -07:00
fs Driver core fixes for 5.15-rc4 2021-10-03 11:10:09 -07:00
include Driver core fixes for 5.15-rc4 2021-10-03 11:10:09 -07:00
init Merge branch 'work.init' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-09-24 10:18:07 -07:00
ipc ipc: remove memcg accounting for sops objects in do_semtimedop() 2021-09-14 10:22:11 -07:00
kernel - Tell the compiler to always inline is_percpu_thread() 2021-10-03 10:49:00 -07:00
lib lib/zlib_inflate/inffast: check config in C to avoid unused function warning 2021-09-24 16:13:35 -07:00
LICENSES LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes" 2021-07-15 06:31:24 -06:00
mm mm: fix uninitialized use in overcommit_policy_handler 2021-09-24 16:13:35 -07:00
net af_unix: fix races in sk_peer_pid and sk_peer_cred accesses 2021-09-30 14:18:40 +01:00
samples kgdb patches for 5.15 2021-09-07 12:08:04 -07:00
scripts kasan: always respect CONFIG_KASAN_STACK 2021-09-24 16:13:35 -07:00
security selinux,smack: fix subjective/objective credential use mixups 2021-09-23 12:30:59 -04:00
sound ALSA: pcsp: Make hrtimer forwarding more robust 2021-09-28 10:58:08 +02:00
tools - Handle symbol relocations properly due to changes in the toolchains 2021-10-03 10:23:54 -07:00
usr .gitignore: prefix local generated files with a slash 2021-05-02 00:43:35 +09:00
virt KVM: Remove tlbs_dirty 2021-09-23 11:01:12 -04:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap mailmap: update email address of Matthias Fuchs and Thomas Körper 2021-08-19 09:39:44 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: move Murali Karicheri to credits 2021-04-29 15:47:30 -07:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Eleven fixes for the ksmbd kernel server, including an important fix disabling weak NTLMv1 authentication, and seven security (improved buffer overflow checks) fixes 2021-10-02 17:43:54 -07:00
Makefile Linux 5.15-rc3 2021-09-26 14:08:19 -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.