The overflow/underflow conditions in pata_macio_qc_prep() should never
happen. But if they do there's no need to kill the system entirely, a
WARN and failing the IO request should be sufficient and might allow the
system to keep running.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>

Kolbjørn and Jonáš reported that their 32-bit PowerMacs were crashing
in pata-macio since commit 09fe2bfa6b83 ("ata: pata_macio: Fix
max_segment_size with PAGE_SIZE == 64K").

For example:

  kernel BUG at drivers/ata/pata_macio.c:544!
  Oops: Exception in kernel mode, sig: 5 [#1]
  BE PAGE_SIZE=4K MMU=Hash SMP NR_CPUS=2 DEBUG_PAGEALLOC PowerMac
  ...
  NIP pata_macio_qc_prep+0xf4/0x190
  LR  pata_macio_qc_prep+0xfc/0x190
  Call Trace:
    0xc1421660 (unreliable)
    ata_qc_issue+0x14c/0x2d4
    __ata_scsi_queuecmd+0x200/0x53c
    ata_scsi_queuecmd+0x50/0xe0
    scsi_queue_rq+0x788/0xb1c
    __blk_mq_issue_directly+0x58/0xf4
    blk_mq_plug_issue_direct+0x8c/0x1b4
    blk_mq_flush_plug_list.part.0+0x584/0x5e0
    __blk_flush_plug+0xf8/0x194
    __submit_bio+0x1b8/0x2e0
    submit_bio_noacct_nocheck+0x230/0x304
    btrfs_work_helper+0x200/0x338
    process_one_work+0x1a8/0x338
    worker_thread+0x364/0x4c0
    kthread+0x100/0x104
    start_kernel_thread+0x10/0x14

That commit increased max_segment_size to 64KB, with the justification
that the SCSI core was already using that size when PAGE_SIZE == 64KB,
and that there was existing logic to split over-sized requests.

However with a sufficiently large request, the splitting logic causes
each sg to be split into two commands in the DMA table, leading to
overflow of the DMA table, triggering the BUG_ON().

With default settings the bug doesn't trigger, because the request size
is limited by max_sectors_kb == 1280, however max_sectors_kb can be
increased, and apparently some distros do that by default using udev
rules.

Fix the bug for 4KB kernels by reverting to the old max_segment_size.

For 64KB kernels the sg_tablesize needs to be halved, to allow for the
possibility that each sg will be split into two.

Fixes: 09fe2bfa6b83 ("ata: pata_macio: Fix max_segment_size with PAGE_SIZE == 64K")
Cc: stable@vger.kernel.org # v6.10+
Reported-by: Kolbjørn Barmen <linux-ppc@kolla.no>
Closes: https://lore.kernel.org/all/62d248bb-e97a-25d2-bcf2-9160c518cae5@kolla.no/
Reported-by: Jonáš Vidra <vidra@ufal.mff.cuni.cz>
Closes: https://lore.kernel.org/all/3b6441b8-06e6-45da-9e55-f92f2c86933e@ufal.mff.cuni.cz/
Tested-by: Kolbjørn Barmen <linux-ppc@kolla.no>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>

This reverts commit 28ab9769117ca944cb6eb537af5599aa436287a4.

Sense data can be in either fixed format or descriptor format.

SAT-6 revision 1, "10.4.6 Control mode page", defines the D_SENSE bit:
"The SATL shall support this bit as defined in SPC-5 with the following
exception: if the D_ SENSE bit is set to zero (i.e., fixed format sense
data), then the SATL should return fixed format sense data for ATA
PASS-THROUGH commands."

The libata SATL has always kept D_SENSE set to zero by default. (It is
however possible to change the value using a MODE SELECT SG_IO command.)

Failed ATA PASS-THROUGH commands correctly respected the D_SENSE bit,
however, successful ATA PASS-THROUGH commands incorrectly returned the
sense data in descriptor format (regardless of the D_SENSE bit).

Commit 28ab9769117c ("ata: libata-scsi: Honor the D_SENSE bit for
CK_COND=1 and no error") fixed this bug for successful ATA PASS-THROUGH
commands.

However, after commit 28ab9769117c ("ata: libata-scsi: Honor the D_SENSE
bit for CK_COND=1 and no error"), there were bug reports that hdparm,
hddtemp, and udisks were no longer working as expected.

These applications incorrectly assume the returned sense data is in
descriptor format, without even looking at the RESPONSE CODE field in the
returned sense data (to see which format the returned sense data is in).

Considering that there will be broken versions of these applications around
roughly forever, we are stuck with being bug compatible with older kernels.

Cc: stable@vger.kernel.org # 4.19+
Reported-by: Stephan Eisvogel <eisvogel@seitics.de>
Reported-by: Christian Heusel <christian@heusel.eu>
Closes: https://lore.kernel.org/linux-ide/0bf3f2f0-0fc6-4ba5-a420-c0874ef82d64@heusel.eu/
Fixes: 28ab9769117c ("ata: libata-scsi: Honor the D_SENSE bit for CK_COND=1 and no error")
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240813131900.1285842-2-cassel@kernel.org
Signed-off-by: Niklas Cassel <cassel@kernel.org>

Pull char / misc and other driver updates from Greg KH:
 "Here is the "big" set of char/misc and other driver subsystem changes
  for 6.11-rc1. Nothing major in here, just loads of new drivers and
  updates. Included in here are:

   - IIO api updates and new drivers added

   - wait_interruptable_timeout() api cleanups for some drivers

   - MODULE_DESCRIPTION() additions for loads of drivers

   - parport out-of-bounds fix

   - interconnect driver updates and additions

   - mhi driver updates and additions

   - w1 driver fixes

   - binder speedups and fixes

   - eeprom driver updates

   - coresight driver updates

   - counter driver update

   - new misc driver additions

   - other minor api updates

  All of these, EXCEPT for the final Kconfig build fix for 32bit
  systems, have been in linux-next for a while with no reported issues.
  The Kconfig fixup went in 29 hours ago, so might have missed the
  latest linux-next, but was acked by everyone involved"

* tag 'char-misc-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (330 commits)
  misc: Kconfig: exclude mrvl-cn10k-dpi compilation for 32-bit systems
  misc: delete Makefile.rej
  binder: fix hang of unregistered readers
  misc: Kconfig: add a new dependency for MARVELL_CN10K_DPI
  virtio: add missing MODULE_DESCRIPTION() macro
  agp: uninorth: add missing MODULE_DESCRIPTION() macro
  spmi: add missing MODULE_DESCRIPTION() macros
  dev/parport: fix the array out-of-bounds risk
  samples: configfs: add missing MODULE_DESCRIPTION() macro
  misc: mrvl-cn10k-dpi: add Octeon CN10K DPI administrative driver
  misc: keba: Fix missing AUXILIARY_BUS dependency
  slimbus: Fix struct and documentation alignment in stream.c
  MAINTAINERS: CC dri-devel list on Qualcomm FastRPC patches
  misc: fastrpc: use coherent pool for untranslated Compute Banks
  misc: fastrpc: support complete DMA pool access to the DSP
  misc: fastrpc: add missing MODULE_DESCRIPTION() macro
  misc: fastrpc: Add missing dev_err newlines
  misc: fastrpc: Use memdup_user()
  nvmem: core: Implement force_ro sysfs attribute
  nvmem: Use sysfs_emit() for type attribute
  ...

Pull ata updates from Niklas Cassel:

 - ATA PASS-THROUGH sense data cleanups and fixes (Igor Pylypiv)

   Store the sense data for ATA PASS-THROUGH commands at the correct
   offset in the sense buffer when using fixed format sense data.

   Cleanup the logic related to generating sense data for PASS-THROUGH
   commands. Generating sense data for PASS-THROUGH commands would
   overwrite any eventual (real) sense data received from the device.

   Honor the D_SENSE bit when generating sense data for PASS-THROUGH
   commands. (The D_SENSE bit can be set by the user, and determines if
   the returned sense data should be in fixed format or descriptor
   format)

 - ata port allocation cleanups (me)

   Assign the ata port print_id at port allocation time, such that the
   ata_port_* print functions can be used earlier in the init call
   chain.

   Change the ata port port print_id to use ida_alloc(), such that
   print_ids will get reused on rmmod + modprobe, instead of being
   incremented indefinitely.

   Remove wrappers that only existed in order to export the internal
   libata functions which they wrapped, and instead export the libata
   functions directly.

 - Update SATA_MOBILE_LPM_POLICY Kconfig default to med_power_with_dipm
   (Mario Limonciello)

   Using this default was not always a good idea before, because it
   would break hot plug support. However, with LPM changes in recent
   kernels, a port marked as external will not enable LPM (in order to
   not break hot plug), so it is now safe to change the default value of
   this Kconfig.

   All major Linux distros have had SATA_MOBILE_LPM_POLICY set to
   med_power_with_dipm for quite a long time

 - Convert ahci-fsl-qoriq device tree binding to yaml format (Frank Li)

* tag 'ata-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/libata/linux:
  dt-bindings: ata: ahci-fsl-qoriq: add fsl,ls1046a-ahci and fsl,ls1012a-ahci
  ata: ahci: Add debug print for external port
  ata,scsi: Remove wrapper ata_sas_port_alloc()
  ata: libata-core: Reuse available ata_port print_ids
  ata: libata: Assign print_id at port allocation time
  ata: libata-core: Remove local_port_no struct member
  ata: libata-sata: Remove superfluous assignment in ata_sas_port_alloc()
  ata: libata-core: Remove support for decreasing the number of ports
  ata: libata: Remove unused function declaration for ata_scsi_detect()
  ata,scsi: Remove wrappers ata_sas_tport_{add,delete}()
  ata: libata-scsi: Check ATA_QCFLAG_RTF_FILLED before using result_tf
  ata: libata-core: Set ATA_QCFLAG_RTF_FILLED in fill_result_tf()
  ata: libata-scsi: Do not pass ATA device id to ata_to_sense_error()
  ata: libata-scsi: Remove redundant sense_buffer memsets
  ata: libata-scsi: Honor the D_SENSE bit for CK_COND=1 and no error
  ata: libata-scsi: Do not overwrite valid sense data when CK_COND=1
  ata: libata-scsi: Fix offsets for the fixed format sense data
  dt-bindings: ata: ahci-fsl-qoriq: convert to yaml format
  ata: Kconfig: Update SATA_MOBILE_LPM_POLICY default to med_power_with_dipm

Pull block updates from Jens Axboe:

 - NVMe updates via Keith:
     - Device initialization memory leak fixes (Keith)
     - More constants defined (Weiwen)
     - Target debugfs support (Hannes)
     - PCIe subsystem reset enhancements (Keith)
     - Queue-depth multipath policy (Redhat and PureStorage)
     - Implement get_unique_id (Christoph)
     - Authentication error fixes (Gaosheng)

 - MD updates via Song
     - sync_action fix and refactoring (Yu Kuai)
     - Various small fixes (Christoph Hellwig, Li Nan, and Ofir Gal, Yu
       Kuai, Benjamin Marzinski, Christophe JAILLET, Yang Li)

 - Fix loop detach/open race (Gulam)

 - Fix lower control limit for blk-throttle (Yu)

 - Add module descriptions to various drivers (Jeff)

 - Add support for atomic writes for block devices, and statx reporting
   for same. Includes SCSI and NVMe (John, Prasad, Alan)

 - Add IO priority information to block trace points (Dongliang)

 - Various zone improvements and tweaks (Damien)

 - mq-deadline tag reservation improvements (Bart)

 - Ignore direct reclaim swap writes in writeback throttling (Baokun)

 - Block integrity improvements and fixes (Anuj)

 - Add basic support for rust based block drivers. Has a dummy null_blk
   variant for now (Andreas)

 - Series converting driver settings to queue limits, and cleanups and
   fixes related to that (Christoph)

 - Cleanup for poking too deeply into the bvec internals, in preparation
   for DMA mapping API changes (Christoph)

 - Various minor tweaks and fixes (Jiapeng, John, Kanchan, Mikulas,
   Ming, Zhu, Damien, Christophe, Chaitanya)

* tag 'for-6.11/block-20240710' of git://git.kernel.dk/linux: (206 commits)
  floppy: add missing MODULE_DESCRIPTION() macro
  loop: add missing MODULE_DESCRIPTION() macro
  ublk_drv: add missing MODULE_DESCRIPTION() macro
  xen/blkback: add missing MODULE_DESCRIPTION() macro
  block/rnbd: Constify struct kobj_type
  block: take offset into account in blk_bvec_map_sg again
  block: fix get_max_segment_size() warning
  loop: Don't bother validating blocksize
  virtio_blk: Don't bother validating blocksize
  null_blk: Don't bother validating blocksize
  block: Validate logical block size in blk_validate_limits()
  virtio_blk: Fix default logical block size fallback
  nvmet-auth: fix nvmet_auth hash error handling
  nvme: implement ->get_unique_id
  block: pass a phys_addr_t to get_max_segment_size
  block: add a bvec_phys helper
  blk-lib: check for kill signal in ioctl BLKZEROOUT
  block: limit the Write Zeroes to manually writing zeroes fallback
  block: refacto blkdev_issue_zeroout
  block: move read-only and supported checks into (__)blkdev_issue_zeroout
  ...

Add a debug print that tells us if LPM is not getting enabled because the
port is external.

Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240703184418.723066-20-cassel@kernel.org
Signed-off-by: Niklas Cassel <cassel@kernel.org>

The ata_sas_port_alloc() wrapper mainly exists in order to export the
internal libata function which it wraps. The secondary reason is that
it initializes some ata_port struct members.

However, ata_sas_port_alloc() is only used in a single location,
sas_ata_init(), which already performs some ata_port struct member
initialization, so it does not make sense to spread this initialization
out over two separate locations.

Thus, remove the wrapper and instead export the libata function directly,
and move the libsas specific ata_port initialization to sas_ata_init(),
which already does some ata_port initialization.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240703184418.723066-19-cassel@kernel.org
Signed-off-by: Niklas Cassel <cassel@kernel.org>

Currently, the ata_port print_ids are increased indefinitely, even when
there are lower ids available.

E.g. on first boot you will have ata1-ata6 assigned.
After a rmmod + modprobe, you will instead have ata7-ata12 assigned.

Move to use the ida_alloc() API, such that print_ids will get reused.
This means that even after a rmmod + modprobe, the ports will be assigned
print_ids ata1-ata6.

Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240703184418.723066-18-cassel@kernel.org
Signed-off-by: Niklas Cassel <cassel@kernel.org>

While the assignment of ap->print_id could have been moved to
ata_host_alloc(), let's simply move it to ata_port_alloc().

If you allocate a port, you want to give it a unique name that can be used
for printing.

By moving the ap->print_id assignment to ata_port_alloc(), means that we
can also remove the ap->print_id assignment from ata_sas_port_alloc().

This will allow a LLD to use the ata_port_*() print functions before
ata_host_register() has been called.

Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240703184418.723066-17-cassel@kernel.org
Signed-off-by: Niklas Cassel <cassel@kernel.org>