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Marc Gonzalez d9245b9296 iommu/arm-smmu-qcom: hide last LPASS SMMU context bank from linux
[ Upstream commit 3a8990b8a778219327c5f8ecf10b5d81377b925a ]

On qcom msm8998, writing to the last context bank of lpass_q6_smmu
(base address 0x05100000) produces a system freeze & reboot.

The hardware/hypervisor reports 13 context banks for the LPASS SMMU
on msm8998, but only the first 12 are accessible...
Override the number of context banks

[    2.546101] arm-smmu 5100000.iommu: probing hardware configuration...
[    2.552439] arm-smmu 5100000.iommu: SMMUv2 with:
[    2.558945] arm-smmu 5100000.iommu: 	stage 1 translation
[    2.563627] arm-smmu 5100000.iommu: 	address translation ops
[    2.568923] arm-smmu 5100000.iommu: 	non-coherent table walk
[    2.574566] arm-smmu 5100000.iommu: 	(IDR0.CTTW overridden by FW configuration)
[    2.580220] arm-smmu 5100000.iommu: 	stream matching with 12 register groups
[    2.587263] arm-smmu 5100000.iommu: 	13 context banks (0 stage-2 only)
[    2.614447] arm-smmu 5100000.iommu: 	Supported page sizes: 0x63315000
[    2.621358] arm-smmu 5100000.iommu: 	Stage-1: 36-bit VA -> 36-bit IPA
[    2.627772] arm-smmu 5100000.iommu: 	preserved 0 boot mappings

Specifically, the crashes occur here:

	qsmmu->bypass_cbndx = smmu->num_context_banks - 1;
	arm_smmu_cb_write(smmu, qsmmu->bypass_cbndx, ARM_SMMU_CB_SCTLR, 0);

and here:

	arm_smmu_write_context_bank(smmu, i);
	arm_smmu_cb_write(smmu, i, ARM_SMMU_CB_FSR, ARM_SMMU_CB_FSR_FAULT);

It is likely that FW reserves the last context bank for its own use,
thus a simple work-around is: DON'T USE IT in Linux.

If we decrease the number of context banks, last one will be "hidden".

Signed-off-by: Marc Gonzalez <mgonzalez@freebox.fr>
Reviewed-by: Caleb Connolly <caleb.connolly@linaro.org>
Reviewed-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20240820-smmu-v3-1-2f71483b00ec@freebox.fr
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-10-17 15:08:13 +02:00
arch x86/syscall: Avoid memcpy() for ia32 syscall_get_arguments() 2024-10-17 15:08:13 +02:00
block blk_iocost: fix more out of bound shifts 2024-10-17 15:08:10 +02:00
certs certs/blacklist_hashes.c: fix const confusion in certs blacklist 2022-06-22 14:13:17 +02:00
crypto crypto: aead,cipher - zeroize key buffer after use 2024-07-18 13:05:38 +02:00
Documentation proc: add config & param to block forcing mem writes 2024-10-17 15:08:12 +02:00
drivers iommu/arm-smmu-qcom: hide last LPASS SMMU context bank from linux 2024-10-17 15:08:13 +02:00
fs proc: add config & param to block forcing mem writes 2024-10-17 15:08:12 +02:00
include netfilter: uapi: NFTA_FLOWTABLE_HOOK is NLA_NESTED 2024-10-17 15:08:06 +02:00
init init/main.c: Fix potential static_command_line memory overflow 2024-05-02 16:23:39 +02:00
io_uring io_uring/io-wq: limit retrying worker initialisation 2024-08-19 05:41:03 +02:00
ipc ipc: replace costly bailout check in sysvipc_find_ipc() 2024-09-04 13:17:44 +02:00
kernel rcuscale: Provide clear error when async specified without primitives 2024-10-17 15:08:13 +02:00
lib debugobjects: Fix conditions in fill_pool() 2024-10-17 15:08:02 +02:00
LICENSES LICENSES/deprecated: add Zlib license text 2020-09-16 14:33:49 +02:00
mm mm: only enforce minimum stack gap size if it's sensible 2024-10-17 15:08:05 +02:00
net tcp: avoid reusing FIN_WAIT2 when trying to find port in connect() process 2024-10-17 15:08:12 +02:00
samples Add gitignore file for samples/fanotify/ subdirectory 2024-08-19 05:41:21 +02:00
scripts scripts: kconfig: merge_config: config files: add a trailing newline 2024-10-17 15:07:32 +02:00
security proc: add config & param to block forcing mem writes 2024-10-17 15:08:12 +02:00
sound ALSA: hdsp: Break infinite MIDI input flush loop 2024-10-17 15:08:13 +02:00
tools perf time-utils: Fix 32-bit nsec parsing 2024-10-17 15:07:52 +02:00
usr usr/include/Makefile: add linux/nfc.h to the compile-test coverage 2022-02-01 17:25:48 +01:00
virt KVM: Always flush async #PF workqueue when vCPU is being destroyed 2024-04-13 12:58:04 +02:00
.clang-format RDMA 5.10 pull request 2020-10-17 11:18:18 -07:00
.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 Remove *.orig pattern from .gitignore 2024-10-17 15:07:59 +02:00
.mailmap mailmap: add two more addresses of Uwe Kleine-König 2020-12-06 10:19:07 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Jason Cooper to CREDITS 2020-11-30 10:20:34 +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 Remove DECnet support from kernel 2023-06-21 15:45:38 +02:00
Makefile Linux 5.10.226 2024-09-12 11:06:51 +02:00
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.