assembly - Accessing bytes out of page -

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i have simple question. i'm not able find answer on own don't have environment test it.

if access 4 bytes on edge of page, happen?

mov eax, dword [0x100000+4095]

what upper 3 bytes when have access page on 0x101000 , when don't?

please help.

what happnes depends on operating system. if have normal memory access, nothing happen. value read whatever there @ time. if access page not allowed, program generate page fault, os has deal with.

if page on disc, because swapped out, os load page, , resume program left off. programm not notice this. if page invalid os raise exception , depending on os may able catch it, or program crash.

if access done on kernel level , can not resolved, os crash kernel panic, or if written, may disable driver, caused it.


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