Re: [4.10, panic, regression] iscsi: null pointer deref at iscsi_tcp_segment_done+0x20d/0x2e0
On Sat, Dec 24, 2016 at 02:17:26PM +0100, Hannes Reinecke wrote: > Christoph, do you have a pointer to your patchset? > Not that I'll be able to do any meaningful work until next year, but having > a look would be nice. Just to get a feeling where you want to head to; I > might be able to work on this start of January. I'll push out a branch once it's revieable and not my current unbisectable mess, should be soon. -- You received this message because you are subscribed to the Google Groups "open-iscsi" group. To unsubscribe from this group and stop receiving emails from it, send an email to open-iscsi+unsubscr...@googlegroups.com. To post to this group, send email to open-iscsi@googlegroups.com. Visit this group at https://groups.google.com/group/open-iscsi. For more options, visit https://groups.google.com/d/optout.
Re: [4.10, panic, regression] iscsi: null pointer deref at iscsi_tcp_segment_done+0x20d/0x2e0
On 12/24/2016 11:07 AM, Christoph Hellwig wrote: On Fri, Dec 23, 2016 at 11:42:45AM -0800, Linus Torvalds wrote: Ugh. This patch is nasty. It's the same SCSI has done for ages - except that is uses a separate kmalloc for the sense buffer. I think we should just fix blk_execute_rq() instead. As you found out below it's not just blk_execute_rq, it's the whole architecture of the BLOCK_PC code, which expects a caller provided sense buffer. But with the way blk-mq allocates request structures we can actually fix it, but I first need to extent the way it allows drivers to allocate private data to the old request code. I've actually already implemented that for SCSI long time ago, and have started to life it to the block layer. Would be cool to have a generic sense buffer. I always found it slightly odd, pretending that 'struct request' is protocol-agnostic and refusing to add a sense data pointer, but at the same time having a field 'sense_len' (which gives the length of what exactly?). Christoph, do you have a pointer to your patchset? Not that I'll be able to do any meaningful work until next year, but having a look would be nice. Just to get a feeling where you want to head to; I might be able to work on this start of January. Cheers, Hannes -- Dr. Hannes Reinecke zSeries & Storage h...@suse.de +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: J. Hawn, J. Guild, F. Imendörffer, HRB 16746 (AG Nürnberg) -- You received this message because you are subscribed to the Google Groups "open-iscsi" group. To unsubscribe from this group and stop receiving emails from it, send an email to open-iscsi+unsubscr...@googlegroups.com. To post to this group, send email to open-iscsi@googlegroups.com. Visit this group at https://groups.google.com/group/open-iscsi. For more options, visit https://groups.google.com/d/optout.
Re: [4.10, panic, regression] iscsi: null pointer deref at iscsi_tcp_segment_done+0x20d/0x2e0
On Fri, Dec 23, 2016 at 11:42:45AM -0800, Linus Torvalds wrote: > Ugh. This patch is nasty. It's the same SCSI has done for ages - except that is uses a separate kmalloc for the sense buffer. > I think we should just fix blk_execute_rq() instead. As you found out below it's not just blk_execute_rq, it's the whole architecture of the BLOCK_PC code, which expects a caller provided sense buffer. But with the way blk-mq allocates request structures we can actually fix it, but I first need to extent the way it allows drivers to allocate private data to the old request code. I've actually already implemented that for SCSI long time ago, and have started to life it to the block layer. Once that is done the callers won't need a sense buffer at all, and can just look at the driver provided one. Which currently is missing in virtio-blk, so we'd need something similar to the above patch anyway. -- You received this message because you are subscribed to the Google Groups "open-iscsi" group. To unsubscribe from this group and stop receiving emails from it, send an email to open-iscsi+unsubscr...@googlegroups.com. To post to this group, send email to open-iscsi@googlegroups.com. Visit this group at https://groups.google.com/group/open-iscsi. For more options, visit https://groups.google.com/d/optout.
Re: [4.10, panic, regression] iscsi: null pointer deref at iscsi_tcp_segment_done+0x20d/0x2e0
On Fri, Dec 23, 2016 at 07:45:45PM -0700, Jens Axboe wrote: > It's not that it's technically hard to fix up, it's more that it's a > pain in the ass to have to do it. For instance, for blk_execute_rq(), we > either should enforce that the caller allocates it dynamically and then > free it, or we need nasty hack where the caller needs to know he has to > free it. Pretty obvious what I would prefer there. > > And yes, there would be a good chunk of other places where this would > nede to be fixed up... My planned rework for the BLOCK_PC code (split all fields for them out of struct request and move them into a separate, driver-allocate structure) would fix this up as a side-effect. I really wanted to get it into 4.10, but I didn't manage to fix it up. I'll try to get it into 4.11 early. -- You received this message because you are subscribed to the Google Groups "open-iscsi" group. To unsubscribe from this group and stop receiving emails from it, send an email to open-iscsi+unsubscr...@googlegroups.com. To post to this group, send email to open-iscsi@googlegroups.com. Visit this group at https://groups.google.com/group/open-iscsi. For more options, visit https://groups.google.com/d/optout.