Re: [2.6 patch] let broken drivers depend on BROKEN{,ON_SMP}

From: Adrian Bunk (bunk_at_fs.tum.de)
Date: 07/30/03

  • Next message: Con Kolivas: "Re: [PATCH] O11int for interactivity"
    Date:	Wed, 30 Jul 2003 12:44:21 +0200
    To: John Bradford <john@grabjohn.com>
    
    

    On Wed, Jul 30, 2003 at 10:11:17AM +0100, John Bradford wrote:
    >...
    > > * Driver does not work, and is thus disabled. If it is not
    > > fixed in the near future, it will be considered to be
    > > OBSOLETE as well.
    > >
    > > CONFIG_BROKEN
    >
    > Please do _NOT_ do this - there is a far more important and worthwhile
    > reason to have a CONFIG_BROKEN than to simply save the few minutes of
    > inconvenience that including a non-compiling option in a kernel build
    > causes.
    >
    > Imagine the situation where a driver such as a SCSI driver builds
    > successfully, but it silently corrupts data under certain, (possibly
    > rare), circumstances.
    >
    > In that case, it's important to warn people that it's broken, because
    > it's not necessarily obvious, and could case significant data loss.
    > If something doesn't compile, it already gives you an error message.
    > The only problem is a few minutes of wasted time.

    You forget one important thing:
    If a _user_ of a stable kernel notices "it doesn't even compile" this
    gives a very bad impression of the quality of the Linux kernel.

    > > * Driver works on uniprocessor but not on SMP and is thus
    > > disabled when compiling for SMP. It is assumed that the
    > > driver will be fixed for SMP if relevant.
    > >
    > > CONFIG_BROKEN_ON_SMP
    >
    > Please _don't_ do this either. It implies that if
    > CONFIG_BROKEN_ON_SMP isn't set, then it's SMP safe - a lot of drivers
    > will NOT have been tested on SMP, so it's a bad thing to assume that
    > is the case.
    >...

    My patch adds BROKEN_ON_SMP only to drivers that don't compile, but if a
    driver causes e.g. data corruption on SMP I don't see a reason against
    letting it depend on BROKEN_ON_SMP.

    > John.

    cu
    Adrian

    -- 
           "Is there not promise of rain?" Ling Tan asked suddenly out
            of the darkness. There had been need of rain for many days.
           "Only a promise," Lao Er said.
                                           Pearl S. Buck - Dragon Seed
    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at  http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at  http://www.tux.org/lkml/
    

  • Next message: Con Kolivas: "Re: [PATCH] O11int for interactivity"

    Relevant Pages

    • Re: [2.6 patch] let broken drivers depend on BROKEN{,ON_SMP}
      ... > * Driver has been replaced by a newer driver, ... The driver _will_ be removed in a future kernel. ... If something doesn't compile, it already gives you an error message. ... > driver will be fixed for SMP if relevant. ...
      (Linux-Kernel)
    • Re: 2.6.1-mm5
      ... Any reason you keep CardServices-compatibility-layer.patch around? ... Having a compat layer for old driver around just for some architectures, ... thus having drivers that only compile on some for no deeper reasons sounds ... send the line "unsubscribe linux-kernel" in ...
      (Linux-Kernel)
    • x86_86 SMP megaraid_mbox hangups and panics.
      ... Having hangs and kernel panics trying to boot AMD64 SMP with an LSI MegaRaid 320-1 card using megaraid_mbox driver. ... I'm trying to boot a monolithic vanilla 2.6.16.1 64-bit SMP on a SuperMicro Opteron server running a dualcore AMD 270 CPU and 8G of RAM. ... 64-bit ACPI disabled - does not work. ... AMD768 system management I/O registers at 0x5000. ...
      (Linux-Kernel)
    • x86: Debug warning: early ioremap leak of 2 areas detected.
      ... Scan SMP from ffd00000 for 1024 bytes. ... ACPI: no DMI BIOS year, acpi=force is required to enable ACPI ... Allocating PCI resources starting at 40000000 ... registered new interface driver usbfs ...
      (Linux-Kernel)
    • Re: no static functions in WDK examples;
      ... information for their products to OCA? ... Windows 2k/XP/2k3 Filesystem and Driver Consulting ... You also end up with a lot of dumps logged ... There is no technical reason not to. ...
      (microsoft.public.win32.programmer.kernel)