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![]() I was writing some MPX test programs and realized that the current design makes it tricky. I did something like: bndcfgu |= bnd_dir | BNDCFGU_ENABLE; xrstor(); printf("xrstor done"); // #BR bounds exception here prctl(MPX_ENABLE_MANAGEMENT); and then compiled the app with "-fcheck-pointer-bounds -mmpx" to enable MPX instrumentation. The problem is that there is MPX instrumentation inserted in to the area of the printf(). The kernel gets a bounds exception and since management isn't yet enabled, it SIGSEGV's. Add a bit to the documentation to explain a way around this and where apps need to be careful. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dave Hansen <dave@sr71.net> Link: http://lkml.kernel.org/r/20141212183835.8C581B3E@viggo.jf.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> |
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i386 | ||
x86_64 | ||
00-INDEX | ||
boot.txt | ||
early-microcode.txt | ||
earlyprintk.txt | ||
entry_64.txt | ||
exception-tables.txt | ||
intel_mpx.txt | ||
mtrr.txt | ||
pat.txt | ||
tlb.txt | ||
usb-legacy-support.txt | ||
zero-page.txt |