Exception table support #212
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wipawel
reviewed
Sep 7, 2021
include/extables.h
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| uint64_t fault_addr; | ||
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| uint64_t fixup; |
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maybe void * would be a better type?
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Actually x86_reg_t would be a better one
include/lib.h
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| volatile bool _read = false; | ||
| uint32_t low, high; | ||
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| asm volatile("1: rdmsr; movq $1, %[read];" |
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this code could be made simpler with asm goto directive, the supplied in label can point to the error condition.
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Please also fix in the |
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nit: please also add empty |
wipawel
requested changes
Sep 7, 2021
wipawel
requested changes
Sep 9, 2021
wipawel
reviewed
Sep 9, 2021
Add support for exception tables. It is possible to register an address that triggers an exception to call an handler, jump to a fixup address or both. Signed-off-by: Daniele Ahmed <[email protected]>
Add new rdmsr_safe and wrmsr_safe. These two functions use exception tables to try performing their operations and returning safely if the operation could not be performed. Signed-off-by: Daniele Ahmed <[email protected]>
In AcpiOsReadable and AcpiOsWriteable the checks for mapped pages and their permissions for reading and writing respectively are performed with exception tables Signed-off-by: Daniele Ahmed <[email protected]>
wipawel
approved these changes
Sep 10, 2021
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Issue #, if available: #6
Description of changes:
This PR adds support for exception tables and uses them to implement rdmsr_safe and wrmsr_safe, that will fail by reporting the error in a boolean variable if the operation on an msr can't be completed due to an exception.
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