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Gavin Shan e3ba51ab24 arm64: tlb: Fix TLBI RANGE operand
KVM/arm64 relies on TLBI RANGE feature to flush TLBs when the dirty
pages are collected by VMM and the page table entries become write
protected during live migration. Unfortunately, the operand passed
to the TLBI RANGE instruction isn't correctly sorted out due to the
commit 117940aa6e ("KVM: arm64: Define kvm_tlb_flush_vmid_range()").
It leads to crash on the destination VM after live migration because
TLBs aren't flushed completely and some of the dirty pages are missed.

For example, I have a VM where 8GB memory is assigned, starting from
0x40000000 (1GB). Note that the host has 4KB as the base page size.
In the middile of migration, kvm_tlb_flush_vmid_range() is executed
to flush TLBs. It passes MAX_TLBI_RANGE_PAGES as the argument to
__kvm_tlb_flush_vmid_range() and __flush_s2_tlb_range_op(). SCALE#3
and NUM#31, corresponding to MAX_TLBI_RANGE_PAGES, isn't supported
by __TLBI_RANGE_NUM(). In this specific case, -1 has been returned
from __TLBI_RANGE_NUM() for SCALE#3/2/1/0 and rejected by the loop
in the __flush_tlb_range_op() until the variable @scale underflows
and becomes -9, 0xffff708000040000 is set as the operand. The operand
is wrong since it's sorted out by __TLBI_VADDR_RANGE() according to
invalid @scale and @num.

Fix it by extending __TLBI_RANGE_NUM() to support the combination of
SCALE#3 and NUM#31. With the changes, [-1 31] instead of [-1 30] can
be returned from the macro, meaning the TLBs for 0x200000 pages in the
above example can be flushed in one shoot with SCALE#3 and NUM#31. The
macro TLBI_RANGE_MASK is dropped since no one uses it any more. The
comments are also adjusted accordingly.

Fixes: 117940aa6e ("KVM: arm64: Define kvm_tlb_flush_vmid_range()")
Cc: stable@kernel.org # v6.6+
Reported-by: Yihuang Yu <yihyu@redhat.com>
Suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Shaoqin Huang <shahuang@redhat.com>
Link: https://lore.kernel.org/r/20240405035852.1532010-2-gshan@redhat.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-04-10 18:22:28 +01:00
Documentation Devicetree fixes for v6.9, part 1: 2024-04-05 14:07:22 -07:00
LICENSES
arch arm64: tlb: Fix TLBI RANGE operand 2024-04-10 18:22:28 +01:00
block block-6.9-20240405 2024-04-05 17:04:11 -07:00
certs This update includes the following changes: 2023-11-02 16:15:30 -10:00
crypto This push fixes a regression that broke iwd as well as a divide by 2024-03-25 10:48:23 -07:00
drivers Miscellaneous x86 fixes: 2024-04-07 09:33:21 -07:00
fs nfsd-6.9 fixes: 2024-04-06 09:37:50 -07:00
include Miscellaneous x86 fixes: 2024-04-07 09:33:21 -07:00
init init: open output files from cpio unpacking with O_LARGEFILE 2024-04-05 11:21:30 -07:00
io_uring io_uring/kbuf: hold io_buffer_list reference over mmap 2024-04-02 19:03:27 -06:00
ipc sysctl changes for v6.9-rc1 2024-03-18 14:59:13 -07:00
kernel Fix various timer bugs: 2024-04-07 09:20:50 -07:00
lib stackdepot: rename pool_index to pool_index_plus_1 2024-04-05 11:21:31 -07:00
mm x86/mm/pat: fix VM_PAT handling in COW mappings 2024-04-05 11:21:31 -07:00
net nfsd-6.9 fixes: 2024-04-06 09:37:50 -07:00
rust Kbuild updates for v6.9 2024-03-21 14:41:00 -07:00
samples Tracing updates for 6.9: 2024-03-18 15:11:44 -07:00
scripts Four small documentation fixes. 2024-04-02 12:44:09 -07:00
security security: Place security_path_post_mknod() where the original IMA call was 2024-04-03 10:21:32 -07:00
sound ASoC: Fixes for v6.9 2024-04-05 08:48:12 +02:00
tools 8 hotfixes, 3 are cc:stable 2024-04-05 13:30:01 -07:00
usr Kbuild updates for v6.8 2024-01-18 17:57:07 -08:00
virt KVM Xen and pfncache changes for 6.9: 2024-03-11 10:42:55 -04:00
.clang-format clang-format: Update with v6.7-rc4's `for_each` macro list 2023-12-08 23:54:38 +01:00
.cocciconfig
.editorconfig Add .editorconfig file for basic formatting 2023-12-28 16:22:47 +09:00
.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: create a list of all built DTB files 2024-02-19 18:20:39 +09:00
.mailmap MAINTAINERS: change vmware.com addresses to broadcom.com 2024-04-05 11:21:31 -07:00
.rustfmt.toml
COPYING
CREDITS Not a ton of stuff happening in the clk framework in this pull request. We got 2024-03-15 11:48:01 -07:00
Kbuild
Kconfig
MAINTAINERS Devicetree fixes for v6.9, part 1: 2024-04-05 14:07:22 -07:00
Makefile Linux 6.9-rc3 2024-04-07 13:22:46 -07:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

README

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.