On Thu, Aug 15, 2013 at 07:53:13PM +0300, Dmitry Kasatkin wrote: > On 15/08/13 19:37, Greg KH wrote: > > On Thu, Aug 15, 2013 at 07:04:54PM +0300, Dmitry Kasatkin wrote: > >> When DEBUG is defined, dev_dbg_ratelimited uses dynamic debug data > >> structures even when CONFIG_DYNAMIC_DEBUG is not defined. > >> It leads to build break. > >> For example, when I try to use dev_dbg_ratelimited in USB code and > >> CONFIG_USB_DEBUG is enabled, but CONFIG_DYNAMIC_DEBUG is not, I get: > >> > >> CC [M] drivers/usb/host/xhci-ring.o > >> drivers/usb/host/xhci-ring.c: In function ‘xhci_queue_intr_tx’: > >> drivers/usb/host/xhci-ring.c:3059:3: error: implicit declaration of function ‘DEFINE_DYNAMIC_DEBUG_METADATA’ [-Werror=implicit-function-declaration] > >> drivers/usb/host/xhci-ring.c:3059:3: error: ‘descriptor’ undeclared (first use in this function) > >> drivers/usb/host/xhci-ring.c:3059:3: note: each undeclared identifier is reported only once for each function it appears in > >> drivers/usb/host/xhci-ring.c:3059:3: error: implicit declaration of function ‘__dynamic_pr_debug’ [-Werror=implicit-function-declaration] > >> drivers/usb/host/xhci-ring.c: In function ‘xhci_queue_isoc_tx_prepare’: > >> drivers/usb/host/xhci-ring.c:3847:3: error: ‘descriptor’ undeclared (first use in this function) > >> cc1: some warnings being treated as errors > >> make[2]: *** [drivers/usb/host/xhci-ring.o] Error 1 > >> make[1]: *** [drivers/usb/host] Error 2 > >> make: *** [drivers/usb/] Error 2 > >> > >> This patch separates definition for CONFIG_DYNAMIC_DEBUG and DEBUG cases. > >> > >> Signed-off-by: Dmitry Kasatkin <d.kasatkin@xxxxxxxxxxx> > >> Cc: stable@xxxxxxxxxxxxxxx > > How is this a stable issue? I don't see how the rules listed in > > Documentation/stable_kernel_rules.txt apply here, what am I missing? > > > > Not to say your patch isn't correct, just that it's not stable material, > > right? > > > > thanks, > > > > greg k-h > > > > There are few drivers which uses dev_dbg_ratelimited(). > In the case someone tries to build kernel with those drivers with DEBUG > enabled and without CONFIG_DYNAMIC_DEBUG, > will get the build break. It will happen also on stable kernel. Do you have specific examples of this happening? Given that this code has been this way for a very long time now, and Randy's excellent 'random .config bot' normally catches this type of thing, I think the applicability to a stable release is pretty low. Please read that Documentation file again about "actual" issues, not just theoretical ones. thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html