On 9/24/2010 9:33 AM, Arnd Bergmann wrote: > On Friday 24 September 2010, Al Viro wrote: >> There are several interesting issues in arch/*/*/*signal* (besides >> shoggoths starting to show up when one reads that code) and I'd been crawling >> through that area for the last few weeks. Here are more or less common >> issues; there are really arch-specific bugs (e.g. roothole on frv that >> used to allow reading kernel memory by setting the right sa_handler), but >> that's a separate story. > > I still plan to make a counterpart to the asm-generic headers with an > example architecture that new architectures can copy from. Signal handling > is one of the areas that I have very limited understanding of. Did you > encounter any architecture that basically gets signal handling right and that > can serve as a positive example to others? > > arch/tile/kernel/signal.c was the last one that got merged and I tried > to direct the maintainer in the right direction as much as I could, but > there are a lot of things I didn't know about. (Sorry for the belated reply.) I set aside this thread to look at when I had a minute, and I believe there is just one of the signal issues present in the tile code. The fix is to reset regs->fault to something other than the "syscall" fault type when exiting from do_signal(), so I'll submit that up for 2.6.37 shortly. Otherwise I think tile is doing things right, though I admit, the signal support is pretty deep magic generally. -- Chris Metcalf, Tilera Corp. http://www.tilera.com -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
