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Yury Norov ea8c66fe8d KVM: x86: hyper-v: fix type of valid_bank_mask
In kvm_hv_flush_tlb(), valid_bank_mask is declared as unsigned long,
but is used as u64, which is wrong for i386, and has been spotted by
LKP after applying "KVM: x86: hyper-v: replace bitmap_weight() with
hweight64()"

https://lore.kernel.org/lkml/20220510154750.212913-12-yury.norov@gmail.com/

But it's wrong even without that patch because now bitmap_weight()
dereferences a word after valid_bank_mask on i386.

>> include/asm-generic/bitops/const_hweight.h:21:76: warning: right shift count >= width of type
+[-Wshift-count-overflow]
      21 | #define __const_hweight64(w) (__const_hweight32(w) + __const_hweight32((w) >> 32))
         |                                                                            ^~
   include/asm-generic/bitops/const_hweight.h:10:16: note: in definition of macro '__const_hweight8'
      10 |          ((!!((w) & (1ULL << 0))) +     \
         |                ^
   include/asm-generic/bitops/const_hweight.h:20:31: note: in expansion of macro '__const_hweight16'
      20 | #define __const_hweight32(w) (__const_hweight16(w) + __const_hweight16((w) >> 16))
         |                               ^~~~~~~~~~~~~~~~~
   include/asm-generic/bitops/const_hweight.h:21:54: note: in expansion of macro '__const_hweight32'
      21 | #define __const_hweight64(w) (__const_hweight32(w) + __const_hweight32((w) >> 32))
         |                                                      ^~~~~~~~~~~~~~~~~
   include/asm-generic/bitops/const_hweight.h:29:49: note: in expansion of macro '__const_hweight64'
      29 | #define hweight64(w) (__builtin_constant_p(w) ? __const_hweight64(w) : __arch_hweight64(w))
         |                                                 ^~~~~~~~~~~~~~~~~
   arch/x86/kvm/hyperv.c:1983:36: note: in expansion of macro 'hweight64'
    1983 |                 if (hc->var_cnt != hweight64(valid_bank_mask))
         |                                    ^~~~~~~~~

CC: Borislav Petkov <bp@alien8.de>
CC: Dave Hansen <dave.hansen@linux.intel.com>
CC: H. Peter Anvin <hpa@zytor.com>
CC: Ingo Molnar <mingo@redhat.com>
CC: Jim Mattson <jmattson@google.com>
CC: Joerg Roedel <joro@8bytes.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Sean Christopherson <seanjc@google.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Vitaly Kuznetsov <vkuznets@redhat.com>
CC: Wanpeng Li <wanpengli@tencent.com>
CC: kvm@vger.kernel.org
CC: linux-kernel@vger.kernel.org
CC: x86@kernel.org
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Message-Id: <20220519171504.1238724-1-yury.norov@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-20 13:03:19 -04:00
arch KVM: x86: hyper-v: fix type of valid_bank_mask 2022-05-20 13:03:19 -04:00
block block: don't print I/O error warning for dead disks 2022-04-15 06:33:03 -06:00
certs Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
crypto for-5.18/64bit-pi-2022-03-25 2022-03-26 12:01:35 -07:00
Documentation Merge branch 'kvm-fixes-for-5.18-rc5' into HEAD 2022-04-29 12:39:34 -04:00
drivers xen: branch for v5.18-rc3 2022-04-17 10:29:10 -07:00
fs Merge branch 'akpm' (patches from Andrew) 2022-04-15 15:57:18 -07:00
include Merge branch 'kvm-fixes-for-5.18-rc5' into HEAD 2022-04-29 12:39:34 -04:00
init Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
ipc fs: allocate inode by using alloc_inode_sb() 2022-03-22 15:57:03 -07:00
kernel A small set of fixes for the timers core: 2022-04-17 09:53:01 -07:00
lib Driver core changes for 5.18-rc2 2022-04-10 09:55:09 -10:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm mm: kmemleak: take a full lowmem check in kmemleak_*_phys() 2022-04-15 14:49:56 -07:00
net Networking fixes for 5.18-rc3, including fixes from wireless and 2022-04-14 11:58:19 -07:00
samples dma-mapping updates for Linux 5.18 2022-03-29 08:50:14 -07:00
scripts hardening fixes for v5.18-rc3 2022-04-12 14:29:40 -10:00
security hardening updates for v5.18-rc1-fix1 2022-03-31 11:43:01 -07:00
sound sound fixes for 5.18-rc3 2022-04-14 11:08:12 -07:00
tools selftests: kvm/x86: Verify the pmu event filter matches the correct event 2022-05-20 07:06:55 -04:00
usr Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
virt KVM: Free new dirty bitmap if creating a new memslot fails 2022-05-20 13:02:05 -04:00
.clang-format genirq/msi: Make interrupt allocation less convoluted 2021-12-16 22:22:20 +01:00
.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 Vasily Averin's email address 2022-04-08 14:20:36 -10:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: replace a Microchip AT91 maintainer 2022-02-09 11:30:01 +01:00
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 ARM: SoC fixes for 5.18, part 2 2022-04-16 16:51:39 -07:00
Makefile Linux 5.18-rc3 2022-04-17 13:57:31 -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.