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Zenghui Yu 53ee75b86b KVM: arm64: vgic-v3: Drop the reporting of GICR_TYPER.Last for userspace
commit 23bde34771 upstream.

It was recently reported that if GICR_TYPER is accessed before the RD base
address is set, we'll suffer from the unset @rdreg dereferencing. Oops...

	gpa_t last_rdist_typer = rdreg->base + GICR_TYPER +
			(rdreg->free_index - 1) * KVM_VGIC_V3_REDIST_SIZE;

It's "expected" that users will access registers in the redistributor if
the RD has been properly configured (e.g., the RD base address is set). But
it hasn't yet been covered by the existing documentation.

Per discussion on the list [1], the reporting of the GICR_TYPER.Last bit
for userspace never actually worked. And it's difficult for us to emulate
it correctly given that userspace has the flexibility to access it any
time. Let's just drop the reporting of the Last bit for userspace for now
(userspace should have full knowledge about it anyway) and it at least
prevents kernel from panic ;-)

[1] https://lore.kernel.org/kvmarm/c20865a267e44d1e2c0d52ce4e012263@kernel.org/

Fixes: ba7b3f1275 ("KVM: arm/arm64: Revisit Redistributor TYPER last bit computation")
Reported-by: Keqian Zhu <zhukeqian1@huawei.com>
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20201117151629.1738-1-yuzenghui@huawei.com
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-02 08:48:07 +01:00
arch x86/microcode/intel: Check patch signature before saving microcode for early loading 2020-11-24 13:27:26 +01:00
block blk-cgroup: Pre-allocate tree node on blkg_conf_prep 2020-11-10 12:35:59 +01:00
certs export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() 2018-08-22 23:21:44 +09:00
crypto crypto: algif_skcipher - EBUSY on aio should be an error 2020-10-29 09:55:01 +01:00
Documentation powerpc/64s: flush L1D after user accesses 2020-11-22 10:02:26 +01:00
drivers s390/dasd: fix null pointer dereference for ERP requests 2020-11-24 13:27:26 +01:00
firmware Fix built-in early-load Intel microcode alignment 2020-01-23 08:21:29 +01:00
fs btrfs: fix lockdep splat when reading qgroup config on mount 2020-12-02 08:48:07 +01:00
include wireless: Use linux/stddef.h instead of stddef.h 2020-12-02 08:48:07 +01:00
init printk: reduce LOG_BUF_SHIFT range for H8300 2020-11-05 11:08:41 +01:00
ipc ipc/util.c: sysvipc_find_ipc() incorrectly updates position index 2020-05-20 08:18:40 +02:00
kernel seccomp: Set PF_SUPERPRIV when checking capability 2020-11-24 13:27:26 +01:00
lib random32: make prandom_u32() output unpredictable 2020-11-18 19:18:52 +01:00
LICENSES LICENSES: Remove CC-BY-SA-4.0 license text 2018-10-18 11:28:50 +02:00
mm mm/userfaultfd: do not access vma->vm_mm after calling handle_userfault() 2020-11-24 13:27:26 +01:00
net mac80211: free sta in sta_info_insert_finish() on errors 2020-11-24 13:27:26 +01:00
samples misc: vop: add round_up(x,4) for vring_size to avoid kernel panic 2020-10-30 10:38:29 +01:00
scripts scripts/setlocalversion: make git describe output more reliable 2020-11-05 11:08:31 +01:00
security selinux: Fix error return code in sel_ib_pkey_sid_slow() 2020-11-18 19:18:50 +01:00
sound ALSA: hda/realtek: Add some Clove SSID in the ALC293(ALC1220) 2020-11-24 13:27:24 +01:00
tools perf event: Check ref_reloc_sym before using it 2020-12-02 08:48:07 +01:00
usr initramfs: restore default compression behavior 2020-04-13 10:44:59 +02:00
virt KVM: arm64: vgic-v3: Drop the reporting of GICR_TYPER.Last for userspace 2020-12-02 08:48:07 +01:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS Documentation/llvm: add documentation on building w/ Clang/LLVM 2020-09-26 18:01:31 +02:00
Makefile Linux 4.19.160 2020-11-24 13:27:27 +01:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -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.
See Documentation/00-INDEX for a list of what is contained in each file.

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.