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Date:   Thu, 10 Aug 2023 00:34:44 +0200 (CEST)
From:   Richard Weinberger <richard@nod.at>
To:     hch <hch@lst.de>
Cc:     Stephan Wurm <stephan.wurm@a-eberle.de>,
        linux-block <linux-block@vger.kernel.org>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        linux-mtd <linux-mtd@lists.infradead.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Johannes Eigner <johannes.eigner@a-eberle.de>
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Subject: Re: ubiblock: null pointer dereference using scatterlist in
 work_queue
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Thread-Topic: ubiblock: null pointer dereference using scatterlist in work_queue
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----- Ursprüngliche Mail -----
> Von: "hch" <hch@lst.de>
> Yes.  So the code needs to stop using sg_virt to work on highmem
> setups and do the equivalent of scsi_kmap_atomic_sg.  Best way
> forward is probably to move scsi_kmap_atomic_sg to lib/scatterlist.c
> (and also convert it to kmap_local instead of kmap_atomic while you're
> at it) and then use that in ubiblock

Will do so! So far I managed to get UBIblock work with scsi_kmap_atomic_sg().
Sadly now with kmap'ed memory a bounce buffer is needed since IO in UBI/MTD can sleep.
Is there a strong reason why scsi_kmap_atomic_sg() needs IRQs disabled?

Thanks,
//richard