intel / Intel-Linux-Processor-Microcode-Data-Files

Other
637 stars 70 forks source link

Can't access RAM from PCIe #22

Closed ranshalit closed 3 years ago

ranshalit commented 4 years ago

Hello,

Is there an known issue of access Xeon's RAM from PCIe (DMA access) ? We observe the issue when using linux 4.x on E5 servers ? We have this issue only with Xeon E5 + Linux, and using other Intel's chip there is no issue. When we use the same BIOS, Chip, with windows , we manage to access RAM's from PCIe (DMA access).

I've tried to search and asked the question, but got no response. Is it a known issue in this chip ? Why is it observed with Linux , but not with Windows ? Should I upgrade BIOS or is it some BIOS parameter that I should configure ?

We also tried to get assistance from Intel's and from Linux kernel, but nothing helped understanding this issue. https://bugzilla.kernel.org/show_bug.cgi?id=205701

Any suggestion bout this issue will help,

Ran

hmh commented 4 years ago

I don't think this is the correct place to ask about this. Maybe the Intel developer forums?

ranshalit commented 4 years ago

I tried the developer zone, but got no response. Is it a microcode issue ?