> Really? > > udelay() seems to use > ... cpu_data(raw_smp_processor_id()).loops_per_jiffy .. Ok that should be a good safety > > ..so it seems that bug trap is already there... because > raw_smp_processor_id() will probably just oops... And I double checked my docs - they say 8 cycles - 1uS Incidentally some of the drivers seem buggy for SMP. The bus locking nature of the inb_p probably hid this but they don't all seem to have sufficient locking to ensure that we don't get back to back cycles without delays Alan -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
- References:
- RFC: outb 0x80 in inb_p, outb_p harmful on some modern AMD64 with MCP51 laptops
- From: "David P. Reed" <[email protected]>
- Re: RFC: outb 0x80 in inb_p, outb_p harmful on some modern AMD64 with MCP51 laptops
- From: Andi Kleen <[email protected]>
- Re: RFC: outb 0x80 in inb_p, outb_p harmful on some modern AMD64 with MCP51 laptops
- From: Alan Cox <[email protected]>
- Re: RFC: outb 0x80 in inb_p, outb_p harmful on some modern AMD64 with MCP51 laptops
- From: Pavel Machek <[email protected]>
- Re: RFC: outb 0x80 in inb_p, outb_p harmful on some modern AMD64 with MCP51 laptops
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- Re: RFC: outb 0x80 in inb_p, outb_p harmful on some modern AMD64 with MCP51 laptops
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- Re: RFC: outb 0x80 in inb_p, outb_p harmful on some modern AMD64 with MCP51 laptops
- From: Alan Cox <[email protected]>
- Re: RFC: outb 0x80 in inb_p, outb_p harmful on some modern AMD64 with MCP51 laptops
- From: Pavel Machek <[email protected]>
- RFC: outb 0x80 in inb_p, outb_p harmful on some modern AMD64 with MCP51 laptops
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