8effeaaf2c
When debugging a kernel panic(), it can be useful to know which CPU features have been detected by the kernel, as some code paths can depend on these (and may have been patched at runtime). This patch adds a notifier to dump the detected CPU caps (as a hex string) at panic(), when we log other information useful for debugging. On a Juno R1 system running v4.12-rc5, this looks like: [ 615.431249] Kernel panic - not syncing: Fatal exception in interrupt [ 615.437609] SMP: stopping secondary CPUs [ 615.441872] Kernel Offset: disabled [ 615.445372] CPU features: 0x02086 [ 615.448522] Memory Limit: none A developer can decode this by looking at the corresponding <asm/cpucaps.h> bits. For example, the above decodes as: * bit 1: ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE * bit 2: ARM64_WORKAROUND_845719 * bit 7: ARM64_WORKAROUND_834220 * bit 13: ARM64_HAS_32BIT_EL0 Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Steve Capper <steve.capper@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> |
||
|---|---|---|
| Documentation | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| 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.