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A comment on TRESOR Runs Encryption Securely Outside RAM. Parent comment

Re:TRESOR Runs Encryption Securely Outside RAM by barrkel on Friday September 27, 2013 @09:56AM (#6457010)
Debug registers are only accessible in Ring 0. I haven't looked at the implementation described, but I'd be surprised if it isn't a kernel module or something equivalent.
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Re:TRESOR Runs Encryption Securely Outside RAM by joe_bleau on Friday September 27, 2013 @11:24AM (#6457453)
Are they available to a JTAG probe? I've not looked at a modern motherboard in ages, but I wouldn't be too surprised to find unpopulated JTAG pads near the CPU.
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Re:TRESOR Runs Encryption Securely Outside RAM by mzs on Friday September 27, 2013 @01:10PM (#6458074)
Only boundary scan on Intel.
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Re:TRESOR Runs Encryption Securely Outside RAM by zerohp on Friday September 27, 2013 @11:32AM (#6457489)
I don't think x86 uses JTAG.
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Re:TRESOR Runs Encryption Securely Outside RAM by joe_bleau on Friday September 27, 2013 @12:15PM (#6457719)
Why not? Even if it doesn't use JTAG for debug, it almost certainly would need it for boundary scan. I just checked volume 1 of the Intel i7 processor family datasheet, and it does show a JTAG port.
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Re:TRESOR Runs Encryption Securely Outside RAM by sanderjd on Friday September 27, 2013 @10:13AM (#6457092)
You are correct - it looks like it is distributed as a kernel patch.
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