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@@ -136,7 +136,7 @@ A: MPX-enabled application will possibly create a lot of bounds tables in
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If we were to preallocate them for the 128TB of user virtual address
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If we were to preallocate them for the 128TB of user virtual address
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space, we would need to reserve 512TB+2GB, which is larger than the
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space, we would need to reserve 512TB+2GB, which is larger than the
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entire virtual address space today. This means they can not be reserved
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entire virtual address space today. This means they can not be reserved
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- ahead of time. Also, a single process's pre-popualated bounds directory
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+ ahead of time. Also, a single process's pre-populated bounds directory
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consumes 2GB of virtual *AND* physical memory. IOW, it's completely
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consumes 2GB of virtual *AND* physical memory. IOW, it's completely
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infeasible to prepopulate bounds directories.
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infeasible to prepopulate bounds directories.
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@@ -151,7 +151,7 @@ A: This would work if we could hook the site of each and every memory
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these calls.
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these calls.
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Q: Could a bounds fault be handed to userspace and the tables allocated
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Q: Could a bounds fault be handed to userspace and the tables allocated
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- there in a signal handler intead of in the kernel?
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+ there in a signal handler instead of in the kernel?
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A: mmap() is not on the list of safe async handler functions and even
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A: mmap() is not on the list of safe async handler functions and even
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if mmap() would work it still requires locking or nasty tricks to
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if mmap() would work it still requires locking or nasty tricks to
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keep track of the allocation state there.
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keep track of the allocation state there.
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Eric Engestrom