About interrupt handler
hi all, I'm begin to learn the Kernel and i'm reading Linux kernel development.It says This is an important point, always keep in mind that all interrupt handler has interrupted other code(possibly even another interrupt handler on a different line).What i am not able to understand is how a interrupt handler be interrupted ? DID NOT it uninterrupted? -- best regards！ cheneydeng___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: About interrupt handler
Original Message From: cheneydeng Sent: 2012年02月22日 星期三 23时38分37秒 To: kernelnewbies Subject: About interrupt handler hi all, I'm begin to learn the Kernel and i'm reading Linux kernel development.It says This is an important point, always keep in mind that all interrupt handler has interrupted other code(possibly even another interrupt handler on a different line).What i am not able to understand is how a interrupt handler be interrupted ? DID NOT it uninterrupted? It has more related to CPU architecture. Generally, while an interrupt handler is being executed, the handler itself can chose to disable or enable external interrupts (i.e, take x86 for example, IF bit for cflags reg controls this.). If IF is enabled, then the interrupt handler currently being executed may be interrupted and then jump to the entry for the coming interrupt. Thanks, -Zhengwang -- best regards！ cheneydeng ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: About interrupt handler
Thanks to all of you~
--
best regards！
cheneydeng
-- Original --
From: Zhengwang Ruanruan.zhengw...@gmail.com;
Date: Thu, Feb 23, 2012 06:07 PM
To: kernelnewbieskernelnewbies@kernelnewbies.org;
Subject: Re: About interrupt handler
Original Message
From: cheneydeng
Sent: 2012年02月22日 星期三 23时38分37秒
To: kernelnewbies
Subject: About interrupt handler
hi all,
I'm begin to learn the Kernel and i'm reading Linux
kernel development.It says This is an important point, always keep
in mind that all interrupt handler has interrupted other
code(possibly even another interrupt handler on a different
line).What i am not able to understand is how a interrupt handler be
interrupted ? DID NOT it uninterrupted?
It has more related to CPU architecture. Generally, while an interrupt
handler is being executed, the handler itself can chose to disable or
enable external interrupts (i.e, take x86 for example, IF bit for cflags
reg controls this.). If IF is enabled, then the interrupt handler currently
being executed may be interrupted and then jump to the entry for the coming
interrupt.
Thanks,
-Zhengwang
--
best regards！
cheneydeng
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Re: Iterating through all the processes in a module
Hi all, thank you very much guys. Your answers helped me to realize what I really wanted to do. Best regards, Arokux ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
RE: SA_INTERRUPT or SA_SHIRQ
Hi Devendra:can you please tell me your kernel version? SA_INTERRUPT is deprecated for many years. it is changed to be IRQF_DISABLED, which is also deprecated since 2.6.35. in kernel 2.6.35, top half interrupt handler will be called with interrupts disabled, and for SA_SHIRQ, it is changed to be IRQF_SHARED, you should check the return value of request_irq() to see whether your irq can be shared with formerregistered irq which use the same int line. suppose you are registering irq19 for usb, and the BT module has reigstered irq19 with IRQF_SHARED flag, then you are lucky enough to reigter correctly for usb. opposite, if BT module registered irq19 without IRQF_SHARED flag, then BT will use irq19 alone, it means your register for usb will fail . Best Regards Date: Wed, 22 Feb 2012 14:56:41 +0530 Subject: SA_INTERRUPT or SA_SHIRQ From: devendra.rawat.si...@gmail.com To: kernelnewbies@kernelnewbies.org Hi All, If I register an ISR using both the flags SA_INTERRUPT and SA_SHIRQ set, what kind of interrupt line will I get a dedicated one or a shared one ? the exact definition is request_irq(dev-pci_dev-irq, soc_intr, SA_INTERRUPT | SA_SHIRQ, MODULE_NAME, dev); thanks in advance, Devendra ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
RE: pagetables used in interrupt context
Hi Subin: for kernel version 2.6.35, ARM architecture, when interrupt occurs, kernel will change from USER/SVC mode to IRQ mode,backup some registers and change to SVC mode immediately, handle the real interrupt handler in SVC mode, which people say in interrupt context.kernel will use the stack(interrupt context) of interrupted thread to handle the interrupt, and there is no MMU operation which do page table switch.so the thread which is interrupted by interrupt, it's kernel mode stack will be choosed as the interrupt context of current interrupt. Date: Tue, 21 Feb 2012 19:18:32 -0700 Subject: Re: pagetables used in interrupt context From: subingangadha...@gmail.com To: dhyla...@gmail.com CC: kernelnewbies@kernelnewbies.org Thank you for clearing my doubt. On Mon, Feb 20, 2012 at 8:39 PM, Dave Hylands dhyla...@gmail.com wrote: Hi Subin, On Mon, Feb 20, 2012 at 6:47 PM, subin gangadharan subingangadha...@gmail.com wrote: Hi All, Please correct me if I am wrong. In linux each process will have its own page tables, so when a interrupt happens processor will switch to interrupt context and execute the proper handler. So my doubt, if this is the case, interrupt hanlder will be using the pagetables of the interrupted process or is there a separate page table for this. Yep - that's right. Conceptually you can imagine that the kernel page tables are replicated in each process, so when the interrupt occurs, the kernel mappings will always be in effect regardless of which task is running. How this is actually achieved may vary from architecture to architecture. -- Dave Hylands Shuswap, BC, Canada http://www.davehylands.com -- With Regards Subin Gangadharan I am not afraid and I am also not afraid of being afraid. ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: SA_INTERRUPT or SA_SHIRQ
Hi All, My comments inline can you please tell me your kernel version? It's linux 2.6.10 SA_INTERRUPT is deprecated for many years. it is changed to be IRQF_DISABLED, which is also deprecated since 2.6.35. in kernel 2.6.35, top half interrupt handler will be called with interrupts disabled, and for SA_SHIRQ, it is changed to be IRQF_SHARED, you should check the return value of request_irq() to see whether your irq can be shared with former registered irq which use the same int line. suppose you are registering irq19 for usb, and the BT module has reigstered irq19 with IRQF_SHARED flag, then you are lucky enough to reigter correctly for usb. opposite, if BT module registered irq19 without IRQF_SHARED flag, then BT will use irq19 alone, it means your register for usb will fail . request_irq( irq, soc_intr, SA_INTERRUPT | SA_SHIRQ, MODULE_NAME, dev); I am assuming that when I specify both SA_INTERRUPT and SA_SHIRQ in request_irq then there are 3 possibilities: 1. If the 'irq' is free then I will be granted the line in SA_INTERRUPT mode i.e all the other maskable interrupts will be disabled when my top_half is executing. 2. If the 'irq' is already granted to some other device in SA_SHIRQ mode then I will also get it in SA_SHIRQ mode i.e all the maskable interrupts enabled execpt from the device whose ISR Top_half is executing. 3. If the 'irq' is already granted to some other device in SA_INTERRUPT mode then my request_irq will fail. I hope this is the right assumption just my only doubt is does the above behavior in any way depends on the CPU arch. i.e is it different for x86 and PPC ? Regards, Devendra ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: pagetables used in interrupt context
On Thu, Feb 23, 2012 at 6:52 AM, 卜弋天 bu...@live.cn wrote: Hi Subin: for kernel version 2.6.35, ARM architecture, when interrupt occurs, kernel will change from USER/SVC mode to IRQ mode,backup some registers and change to SVC mode immediately, handle the real interrupt handler in SVC mode, which people say in interrupt context. kernel will use the stack(interrupt context) of interrupted thread to handle the interrupt, and there is no MMU operation which do page table switch. so the thread which is interrupted by interrupt, it's kernel mode stack will be choosed as the interrupt context of current interrupt. Thanks ! thats a terse explanation! Can you please mention why we do not have a IRQ stack (in terms of size of the stack) to do the processing? Date: Tue, 21 Feb 2012 19:18:32 -0700 Subject: Re: pagetables used in interrupt context From: subingangadha...@gmail.com To: dhyla...@gmail.com CC: kernelnewbies@kernelnewbies.org Thank you for clearing my doubt. On Mon, Feb 20, 2012 at 8:39 PM, Dave Hylands dhyla...@gmail.com wrote: Hi Subin, On Mon, Feb 20, 2012 at 6:47 PM, subin gangadharan subingangadha...@gmail.com wrote: Hi All, Please correct me if I am wrong. In linux each process will have its own page tables, so when a interrupt happens processor will switch to interrupt context and execute the proper handler. So my doubt, if this is the case, interrupt hanlder will be using the pagetables of the interrupted process or is there a separate page table for this. Yep - that's right. Conceptually you can imagine that the kernel page tables are replicated in each process, so when the interrupt occurs, the kernel mappings will always be in effect regardless of which task is running. How this is actually achieved may vary from architecture to architecture. -- Dave Hylands Shuswap, BC, Canada http://www.davehylands.com -- With Regards Subin Gangadharan I am not afraid and I am also not afraid of being afraid. ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
RE: pagetables used in interrupt context
Hi : for ARM architecture, from the point of my view, interrupt can be handled in IRQ, SVC, or SYSTEM modes.1.if kernel handles interrupt in IRQ mode, it can use separate specific stack of IRQ mode to handle interrupt,but it cannot support nest interupt, suppose you are running interrupt handler in IRQ mode, a new coming interrupt will corrupt the lr_irq which is used for current function.2. if kernel handles interrupt in SYSTEM mode, the sequences will be : hardware interrupt occurs--IRQ mode--SYSTEM mode --call interrupt handler. kernel can support nest interrupt well by this way, the problem is SYSTEM mode use the same register with USER mode, which means kernel will use the interrupted thread's user mode stack, this will leake information of kernel to user space, so it is not a good idea, although i did this for many years for OMAP chipset(the OS is not linux, it is mixed by REX and my own design.).3. Linux kernel choose the last one, handle interrupt in SVC mode, which can support nest interrupt if it wants(2.6.35 does not support this). and it is very simple to use the interrupted thread's kernel mode stack as the interrupt context. if kernel use a specific stack which is for interrupt only, the sequences will be : hardware interrupt occurs--IRQ mode--SVC mode--backup sp register of interrupted thread to it's TCB---set sp register to be the specific kernel stack address--call interrupt handler---restore sp of interrupted thread---return from interrupt.this is a little complicated compared with the current design. so i agree with the current design. Best Regards Date: Thu, 23 Feb 2012 08:41:28 -0600 Subject: Re: pagetables used in interrupt context From: c.a.subraman...@gmail.com To: bu...@live.cn CC: dhyla...@gmail.com; subingangadha...@gmail.com; kernelnewbies@kernelnewbies.org On Thu, Feb 23, 2012 at 6:52 AM, 卜弋天 bu...@live.cn wrote: Hi Subin: for kernel version 2.6.35, ARM architecture, when interrupt occurs, kernel will change from USER/SVC mode to IRQ mode,backup some registers and change to SVC mode immediately, handle the real interrupt handler in SVC mode, which people say in interrupt context. kernel will use the stack(interrupt context) of interrupted thread to handle the interrupt, and there is no MMU operation which do page table switch. so the thread which is interrupted by interrupt, it's kernel mode stack will be choosed as the interrupt context of current interrupt. Thanks ! thats a terse explanation! Can you please mention why we do not have a IRQ stack (in terms of size of the stack) to do the processing? Date: Tue, 21 Feb 2012 19:18:32 -0700 Subject: Re: pagetables used in interrupt context From: subingangadha...@gmail.com To: dhyla...@gmail.com CC: kernelnewbies@kernelnewbies.org Thank you for clearing my doubt. On Mon, Feb 20, 2012 at 8:39 PM, Dave Hylands dhyla...@gmail.com wrote: Hi Subin, On Mon, Feb 20, 2012 at 6:47 PM, subin gangadharan subingangadha...@gmail.com wrote: Hi All, Please correct me if I am wrong. In linux each process will have its own page tables, so when a interrupt happens processor will switch to interrupt context and execute the proper handler. So my doubt, if this is the case, interrupt hanlder will be using the pagetables of the interrupted process or is there a separate page table for this. Yep - that's right. Conceptually you can imagine that the kernel page tables are replicated in each process, so when the interrupt occurs, the kernel mappings will always be in effect regardless of which task is running. How this is actually achieved may vary from architecture to architecture. -- Dave Hylands Shuswap, BC, Canada http://www.davehylands.com -- With Regards Subin Gangadharan I am not afraid and I am also not afraid of being afraid. ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: pagetables used in interrupt context
Hi , can support nest interrupt if it wants(2.6.35 does not support this). and it is very simple to use the interrupted thread's kernel mode stack as the interrupt context. if kernel use a specific stack which is for interrupt Thanks for the crystal clear explanation of the page table usage in interrupt context. I have one more doubt, so in 2.6.35 as you said it doesn't support nested interrupt, does it mean that all other interrupts are completely disabled, (I mean no other can interrupt the processor) while executing an interrupt handler. 2012/2/23 卜弋天 bu...@live.cn: Hi : for ARM architecture, from the point of my view, interrupt can be handled in IRQ, SVC, or SYSTEM modes. 1.if kernel handles interrupt in IRQ mode, it can use separate specific stack of IRQ mode to handle interrupt,but it cannot support nest interupt, suppose you are running interrupt handler in IRQ mode, a new coming interrupt will corrupt the lr_irq which is used for current function. 2. if kernel handles interrupt in SYSTEM mode, the sequences will be : hardware interrupt occurs--IRQ mode--SYSTEM mode --call interrupt handler. kernel can support nest interrupt well by this way, the problem is SYSTEM mode use the same register with USER mode, which means kernel will use the interrupted thread's user mode stack, this will leake information of kernel to user space, so it is not a good idea, although i did this for many years for OMAP chipset(the OS is not linux, it is mixed by REX and my own design.). 3. Linux kernel choose the last one, handle interrupt in SVC mode, which can support nest interrupt if it wants(2.6.35 does not support this). and it is very simple to use the interrupted thread's kernel mode stack as the interrupt context. if kernel use a specific stack which is for interrupt only, the sequences will be : hardware interrupt occurs--IRQ mode--SVC mode--backup sp register of interrupted thread to it's TCB---set sp register to be the specific kernel stack address--call interrupt handler---restore sp of interrupted thread---return from interrupt. this is a little complicated compared with the current design. so i agree with the current design. Best Regards Date: Thu, 23 Feb 2012 08:41:28 -0600 Subject: Re: pagetables used in interrupt context From: c.a.subraman...@gmail.com To: bu...@live.cn CC: dhyla...@gmail.com; subingangadha...@gmail.com; kernelnewbies@kernelnewbies.org On Thu, Feb 23, 2012 at 6:52 AM, 卜弋天 bu...@live.cn wrote: Hi Subin: for kernel version 2.6.35, ARM architecture, when interrupt occurs, kernel will change from USER/SVC mode to IRQ mode,backup some registers and change to SVC mode immediately, handle the real interrupt handler in SVC mode, which people say in interrupt context. kernel will use the stack(interrupt context) of interrupted thread to handle the interrupt, and there is no MMU operation which do page table switch. so the thread which is interrupted by interrupt, it's kernel mode stack will be choosed as the interrupt context of current interrupt. Thanks ! thats a terse explanation! Can you please mention why we do not have a IRQ stack (in terms of size of the stack) to do the processing? Date: Tue, 21 Feb 2012 19:18:32 -0700 Subject: Re: pagetables used in interrupt context From: subingangadha...@gmail.com To: dhyla...@gmail.com CC: kernelnewbies@kernelnewbies.org Thank you for clearing my doubt. On Mon, Feb 20, 2012 at 8:39 PM, Dave Hylands dhyla...@gmail.com wrote: Hi Subin, On Mon, Feb 20, 2012 at 6:47 PM, subin gangadharan subingangadha...@gmail.com wrote: Hi All, Please correct me if I am wrong. In linux each process will have its own page tables, so when a interrupt happens processor will switch to interrupt context and execute the proper handler. So my doubt, if this is the case, interrupt hanlder will be using the pagetables of the interrupted process or is there a separate page table for this. Yep - that's right. Conceptually you can imagine that the kernel page tables are replicated in each process, so when the interrupt occurs, the kernel mappings will always be in effect regardless of which task is running. How this is actually achieved may vary from architecture to architecture. -- Dave Hylands Shuswap, BC, Canada http://www.davehylands.com -- With Regards Subin Gangadharan I am not afraid and I am also not afraid of being afraid. ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies ___ Kernelnewbies mailing list
How to debug system freeze?
Hi, I'm experiencing strange bug when I close lid of my laptop - system freezes (no reaction on keys, no response form ssh) hard and displays some strange colour effects. The kernel log (after reboot) shows nothing. My question is - how to debug it? Maybe there's a way to track last called kernel function or something similar? Thanks, Lukasz Sowa ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: The 2.6.32 Linux kernel patches
Also I'm new to git, does any one have a good tutorial on this with focus on Linux kernel development? Here's a couple of guides with hints I've found useful: http://linux.yyz.us/git-howto.html http://progit.org/ HTH, Cheers Julie ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
RE: pagetables used in interrupt context
Hi Subin: i am not familiar with other architecture, but for ARM, Linux Kernel 2.6.35, i checked the function handle_level_irq()and handle_edge_irq() in chip.c, both of them will call handle_IRQ_event() which is in handle.c. and the function handle_IRQ_event() will call the interrupt handler written by user. Kernel does not open interrupt(ARM CPSR I bit)when calling interrupt handler in handle_IRQ_event() function. this is only for top-half interrupt handling. for bottom-half, it is no doubt that the interrupt will be opened. so if you register a interrupt by request_irq(), the interrupt handler will be called with irq disabled. i tested on Cortex-A9 dual core platform, it is right. Date: Thu, 23 Feb 2012 11:12:06 -0600 Subject: Re: pagetables used in interrupt context From: subingangadha...@gmail.com To: bu...@live.cn CC: c.a.subraman...@gmail.com; dhyla...@gmail.com; kernelnewbies@kernelnewbies.org Hi , can support nest interrupt if it wants(2.6.35 does not support this). and it is very simple to use the interrupted thread's kernel mode stack as the interrupt context. if kernel use a specific stack which is for interrupt Thanks for the crystal clear explanation of the page table usage in interrupt context. I have one more doubt, so in 2.6.35 as you said it doesn't support nested interrupt, does it mean that all other interrupts are completely disabled, (I mean no other can interrupt the processor) while executing an interrupt handler. 2012/2/23 卜弋天 bu...@live.cn: Hi : for ARM architecture, from the point of my view, interrupt can be handled in IRQ, SVC, or SYSTEM modes. 1.if kernel handles interrupt in IRQ mode, it can use separate specific stack of IRQ mode to handle interrupt,but it cannot support nest interupt, suppose you are running interrupt handler in IRQ mode, a new coming interrupt will corrupt the lr_irq which is used for current function. 2. if kernel handles interrupt in SYSTEM mode, the sequences will be : hardware interrupt occurs--IRQ mode--SYSTEM mode --call interrupt handler. kernel can support nest interrupt well by this way, the problem is SYSTEM mode use the same register with USER mode, which means kernel will use the interrupted thread's user mode stack, this will leake information of kernel to user space, so it is not a good idea, although i did this for many years for OMAP chipset(the OS is not linux, it is mixed by REX and my own design.). 3. Linux kernel choose the last one, handle interrupt in SVC mode, which can support nest interrupt if it wants(2.6.35 does not support this). and it is very simple to use the interrupted thread's kernel mode stack as the interrupt context. if kernel use a specific stack which is for interrupt only, the sequences will be : hardware interrupt occurs--IRQ mode--SVC mode--backup sp register of interrupted thread to it's TCB---set sp register to be the specific kernel stack address--call interrupt handler---restore sp of interrupted thread---return from interrupt. this is a little complicated compared with the current design. so i agree with the current design. Best Regards Date: Thu, 23 Feb 2012 08:41:28 -0600 Subject: Re: pagetables used in interrupt context From: c.a.subraman...@gmail.com To: bu...@live.cn CC: dhyla...@gmail.com; subingangadha...@gmail.com; kernelnewbies@kernelnewbies.org On Thu, Feb 23, 2012 at 6:52 AM, 卜弋天 bu...@live.cn wrote: Hi Subin: for kernel version 2.6.35, ARM architecture, when interrupt occurs, kernel will change from USER/SVC mode to IRQ mode,backup some registers and change to SVC mode immediately, handle the real interrupt handler in SVC mode, which people say in interrupt context. kernel will use the stack(interrupt context) of interrupted thread to handle the interrupt, and there is no MMU operation which do page table switch. so the thread which is interrupted by interrupt, it's kernel mode stack will be choosed as the interrupt context of current interrupt. Thanks ! thats a terse explanation! Can you please mention why we do not have a IRQ stack (in terms of size of the stack) to do the processing? Date: Tue, 21 Feb 2012 19:18:32 -0700 Subject: Re: pagetables used in interrupt context From: subingangadha...@gmail.com To: dhyla...@gmail.com CC: kernelnewbies@kernelnewbies.org Thank you for clearing my doubt. On Mon, Feb 20, 2012 at 8:39 PM, Dave Hylands dhyla...@gmail.com wrote: Hi Subin, On Mon, Feb 20, 2012 at 6:47 PM, subin gangadharan subingangadha...@gmail.com wrote: Hi All, Please correct me if I am wrong. In linux each process will have its own page tables, so when a interrupt happens processor will switch to interrupt context and execute the proper handler. So my doubt, if this is the case, interrupt hanlder will be using the
Re: Semaphore
Imagine a driver which only one app can use at a time (perhaps a serial port). The kernel will take a lock when the user space app open()s the device node and release it when it close()s. If the app segfaults in between the open() and close() the lock will still get released. The kernel always cleans up open files for stopped processes, regardless of how they stop. During this cleanup the kernel will close() the device node, and as a result the driver will release the lock. Can you please point to some code in Linux Kernel that does the job? Thanks, --- KostaZ ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
