mirror of https://github.com/acidanthera/audk.git
6c9a3d4233
Cache maintenance operations by set/way are only intended to be used in the context of on/offlining a core, while it has been taken out of the coherency domain. Any use intended to ensure that the contents of the cache have made it to main memory is unreliable, since cacheline migration and non-architected system caches may cause these contents to linger elsewhere, without being visible in main memory once the MMU and caches are disabled. In KVM on Linux, there are horrid hacks in place to ensure that such set/way operations are trapped, and replaced with a single by-VA clean/invalidate of the entire guest VA space once the MMU state changes, which can be costly, and is unnecessary if we manage the caches a bit more carefully, and perform maintenance by virtual address only. So let's get rid of the call to ArmInvalidateDataCache () in the PrePeiCore startup code, and instead, invalidate the temporary RAM region by virtual address, which is the only memory region we will be touching with the caches and MMU both disabled and enabled, which will lead to data corruption if data written with the MMU off is shadowed by clean, stale cachelines that stick around when the MMU is enabled again. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@arm.com> Reviewed-by: Leif Lindholm <leif@nuviainc.com> Acked-by: Laszlo Ersek <lersek@redhat.com> |
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| .. | ||
| Drivers | ||
| Include/Library | ||
| Library | ||
| MemoryInitPei | ||
| PlatformPei | ||
| PrePeiCore | ||
| PrePi | ||
| Scripts | ||
| ArmPlatformPkg.dec | ||
| ArmPlatformPkg.dsc | ||