638f863dbb
When we're updating a register's sys_val, we use arm64_ftr_value() to find the new field value. We use cpuid_feature_extract_field() to find the new value, but this implicitly assumes a 4-bit field, so we may extract more bits than we mean to for fields like CTR_EL0.L1ip. This affects update_cpu_ftr_reg(), where we may extract erroneous values for ftr_cur and ftr_new. Depending on the additional bits extracted in either case, we may erroneously detect that the value is mismatched, and we'll try to compute a new safe value. Dependent on these extra bits and feature type, arm64_ftr_safe_value() may pessimistically select the always-safe value, or may erroneously choose either the extracted cur or new value as the safe option. The extra bits will subsequently be masked out in arm64_ftr_set_value(), so we may choose a higher value, yet write back a lower one. Fix this by passing the width down explicitly in arm64_ftr_value(), so we always extract the correct amount. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> |
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| arch | ||
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| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
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| COPYING | ||
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| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. 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.