Page Fault

Question

Why is accessing a dirty page considered a page fault?

Comments

If a page needs to be accessed, it is in main memory and if it is dirty it will be a page hit and not a page fault.

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https://gateoverflow.in/73973/%23operating-system please check this here it is stated that if a page is dirty it causes a page fault

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I could conclude that irrespective of the available page by dirty of not, if we try to write on a read only page then we may get a page fault.

Answer 1

As far as my knowledge goes, accessing a page which has its dirty bit set doesn't lead to a page fault; it's valid access. Page fault occurs when the requested page is either unavailable in RAM, or if the page is in RAM but is unaccessible due to restricted permissions.

Comments

The answer which you gave is a paradox!

first you said, "accessing a page which has its dirty bit set doesn't lead to a page fault"

the you said,"if the page is in RAM but is unaccessible due to restricted permissions."

In this the restricted permission will set the dirty bit  and will lead to page fault? right