How to understand this sentence in the PM spec--"Alternatively, an implementation may choose to "waste" TLB capacity by having up to 4 duplicate entries for each page."

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How to understand this sentence in the PM spec--"Alternatively, an implementation may choose to "waste" TLB capacity by having up to 4 duplicate entries for each page." #1721

Open chara811 opened 1 week ago

chara811 commented 1 week ago

When vsatp=bare,hgatp=sv48x4,GPA[49:48] =00,01,10 or 11,but we can't see these 2 bits, so there will be 4 duplicate pages. Can I understand it this way?

gfavor commented 1 week ago

Since this a PM-specific question, I suggest asking this on the tech-j-ext@lists.risc-v.org email list to get a good answer.