Re: [RFC PATCH 1/1] riscv: mm: notify remote harts about mmu cache updates

[Sergey Matyukevich <geomatsi@gmail.com>]

Hi Prabhakar,

> Hi Sergey,
> 
> On Mon, Aug 29, 2022 at 9:53 PM Sergey Matyukevich <geomatsi@gmail.com> wrote:
> >
> > From: Sergey Matyukevich <sergey.matyukevich@syntacore.com>
> >
> > Current implementation of update_mmu_cache function performs local TLB
> > flush. It does not take into account ASID information. Besides, it does
> > not take into account other harts currently running the same mm context
> > or possible migration of the running context to other harts. Meanwhile
> > TLB flush is not performed for every context switch if ASID support
> > is enabled.
> >
> > Patch [1] proposed to add ASID support to update_mmu_cache to avoid
> > flushing local TLB entirely. This patch takes into account other
> > harts currently running the same mm context as well as possible
> > migration of this context to other harts.
> >
> > For this purpose the approach from flush_icache_mm is reused. Remote
> > harts currently running the same mm context are informed via SBI calls
> > that they need to flush their local TLBs. All the other harts are marked
> > as needing a deferred TLB flush when this mm context runs on them.
> >
> > [1] https://lore.kernel.org/linux-riscv/20220821013926.8968-1-tjytimi@163.com/
> >
> > Signed-off-by: Sergey Matyukevich <sergey.matyukevich@syntacore.com>
> > ---
> >  arch/riscv/include/asm/mmu.h      |  2 ++
> >  arch/riscv/include/asm/pgtable.h  |  2 +-
> >  arch/riscv/include/asm/tlbflush.h | 18 ++++++++++++++++++
> >  arch/riscv/mm/context.c           | 10 ++++++++++
> >  arch/riscv/mm/tlbflush.c          | 28 +++++++++++-----------------
> >  5 files changed, 42 insertions(+), 18 deletions(-)
> >
> I couldn't find your latest patch in my mailbox so I'm replying to this one.
> 
> I merged Palmer's for-next branch and when running tests on eMMC with
> bonnie++ on the Renesas RZ/Five SoC I am seeing the below issues:
> 
> root@smarc-rzfive:/lava-testing# ./emmc_t_002.sh
> 
> Welcome to fdisk (util-linux 2.35.1).
> Changes will remain in memory only, until you decide to write them.
> Be careful before using the write command.
> 
> [   40.809677]  mmcblk0: p1
> 
> Command (m for help): Created a new DOS disklabel with disk identifier
> 0xf4682ae9.
> 
> Command (m for help): Partition type
>    p   primary (0 primary, 0 extended, 4 free)
>    e   extended (container for logical partitions)
> Select (default p): Partition number (1-4, default 1): First sector
> (2048-124321791, default 2048): Last sector, +/-sectors or
> +/-size{K,M,G,T,P} (2048-124321791, default 124321791):
> Created a new partition 1 of type 'Linux' and of size 59.3 GiB.
> Partition #1 contains a ext4 signature.
> 
> Command (m for help):
> The partition table has been altered.
> Calling ioctl() to re-read partition table.
> [   40.945583]  mmcblk0: p1
> Syncing disks.
> 
> mke2fs 1.45.7 (28-Jan-2021)
> /dev/mmcblk0p1 contains a ext4 file system
>         last mounted on /tmp/tmp.PDgTkhohqt/mnt on Fri Dec 16 19:48:34 2022
> Discarding device blocks: done
> Creating filesystem with 15539968 4k blocks and 3891200 inodes
> Filesystem UUID: 6effbf47-2d7a-4eb8-b2dc-1333b848e449
> Superblock backups stored on blocks:
>         32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
>         4096000, 7962624, 11239424
> 
> Allocating group tables: done
> Writing inode tables: done
> Creating journal (65536 blocks): done
> Writing superblocks and filesystem accounting information: done
> 
> e2fsck 1.45.7 (28-Jan-2021)
> Pass 1: Checking inodes, blocks, and sizes
> Pass 2: Checking directory structure
> Pass 3: Checking directory connectivity
> Pass 4: Checking reference counts
> Pass 5: Checking group summary information
> /dev/mmcblk0p1: 11/3891200 files (0.0% non-contiguous), 323121/15539968 blocks
> [   91.521828] EXT4-fs (mmcblk0p1): mounted filesystem
> 6effbf47-2d7a-4eb8-b2dc-1333b848e449 with ordered data mode. Quota
> mode: disabled.
> Using uid:0, gid:0.
> Writing with putc()...[  131.775220] do_trap: 3 callbacks suppressed
> [  131.775245] sd-resolve[128]: unhandled signal 11 code 0x1 at
> 0x0000000000000060 in libpthread-2.28.so[3fa6d80000+13000]
> [  131.790382] CPU: 0 PID: 128 Comm: sd-resolve Not tainted
> 6.1.0-11009-gf4e9a8cdc25b #167
> [  131.798386] Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT)
> [  131.804999] epc : 0000003fa6d8eeac ra : 0000003fa6f4a76c sp :
> 0000003fa6b8c330
> [  131.812214]  gp : 0000002aacc1cb88 tp : 0000003fa6b92810 t0 :
> 0000000000000022
> [  131.819432]  t1 : 0000003fa6e7f0ec t2 : 0000003fa6b8b290 s0 :
> 0000003fa6b8c850
> [  131.826669]  s1 : 0000002aacc1f430 a0 : 000000000000000a a1 :
> 0000003fa6b8c3b8
> [  131.833891]  a2 : 0000000000004000 a3 : 0000000000000000 a4 :
> 0000000000000020
> [  131.841110]  a5 : 0000000000000002 a6 : 0000003fa6b8c360 a7 :
> 0000000000000007
> [  131.848328]  s2 : ffffffffffffb000 s3 : ffffffffffffd3d0 s4 :
> 0000003fa6fe0918
> [  131.855561]  s5 : 0000003fa6b8ec20 s6 : 0000003fa6b8c440 s7 :
> fffffffffffffffd
> [  131.862783]  s8 : 0000003fa6b8c420 s9 : 000000000000000a s10:
> 0000000000000000
> [  131.870001]  s11: 0000003fa6fe2090 t3 : 0000003fa6d8eeaa t4 :
> 00000009a331f45c
> [  131.877219]  t5 : 000000000000003f t6 : 0000000000000000
> [  131.882548] status: 8000000200006020 badaddr: 0000000000000060
> cause: 000000000000000d
> [  131.891349] systemd-journal[87]: unhandled signal 11 code 0x1 at
> 0x00000000000000c8 in systemd-journald[2abd710000+1b000]
> [  131.902382] CPU: 0 PID: 87 Comm: systemd-journal Not tainted
> 6.1.0-11009-gf4e9a8cdc25b #167
> [  131.910731] Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT)
> [  131.917359] epc : 0000002abd7167e0 ra : 0000002abd7179e4 sp :
> 0000003fd65416c0
> [  131.924578]  gp : 0000002abd72e120 tp : 0000003fbea1f720 t0 :
> 3534616138333466
> [  131.931796]  t1 : ffffffffffffe000 t2 : 000000000000000d s0 :
> 0000003fd65416c0
> [  131.939014]  s1 : 0000003fd65437a8 a0 : 0000000000000009 a1 :
> 0000003fd65416c0
> [  131.946232]  a2 : 0000000000002000 a3 : 0000003fd65437a8 a4 :
> 0000003fd65436c8
> [  131.953450]  a5 : 0000003fd65436d0 a6 : 0000000000000083 a7 :
> 0000000000000018
> [  131.960668]  s2 : 0000003fbee6c918 s3 : 0000003fd6543708 s4 :
> 0000003fd6543700
> [  131.967885]  s5 : 0000002abd724718 s6 : 0000002abd7247d8 s7 :
> 0000000000000000
> [  131.975102]  s8 : ffffffffffffffff s9 : 0000002ad2397120 s10:
> 0000000000000000
> [  131.982319]  s11: 0000003fe5aad418 t3 : 0000003fbed75364 t4 :
> 00000009a7934adc
> [  131.989564]  t5 : 00000000001ea8b0 t6 : 3463396363613637
> [  131.994883] status: 0000000200004020 badaddr: 00000000000000c8
> cause: 000000000000000d
> [  132.003911] audit: type=1701 audit(1671220069.615:11):
> auid=4294967295 uid=0 gid=0 ses=4294967295 pid=87
> comm="systemd-journal" exe="/lib/systemd/systemd-journald" sig=11
> res=1
> [  132.024142] systemd[1]: unhandled signal 11 code 0x1 at
> 0xffffffac2b2a2928 in ld-2.28.so[3f83a6e000+17000]
> [  132.033946] CPU: 0 PID: 1 Comm: systemd Not tainted
> 6.1.0-11009-gf4e9a8cdc25b #167
> [  132.041563] Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT)
> [  132.048198] epc : 0000003f83a7a81c ra : 0000003f83a7a992 sp :
> 0000003fe5aad570
> [  132.055419]  gp : 0000002ad234ad28 tp : 0000003f83628e70 t0 :
> 0000000000a9919e
> [  132.062635]  t1 : 0000003f8391f7dc t2 : 0000000000000000 s0 :
> 0000003f83a664d0
> [  132.069852]  s1 : 0000003f83a85918 a0 : 0000000000000001 a1 :
> 0000003f83a20940
> [  132.077068]  a2 : 0000003f83629680 a3 : 0000000000000073 a4 :
> 0000000000000001
> [  132.084284]  a5 : 0000003f83a87090 a6 : 000000000000002f a7 :
> 0000000000062164
> [  132.091501]  s2 : 0000002ad22cdce0 s3 : 0000003f83a85918 s4 :
> 0000000000000006
> [  132.098722]  s5 : 0000000000000002 s6 : 0000003f83a85918 s7 :
> 0000000000001000
> [  132.105939]  s8 : 0000003fe5aad750 s9 : 0000003fe5aad9e0 s10:
> 0000002ad22fdd60
> [  132.113155]  s11: 2f2e2d2c2b2a2928 t3 : 0000003f83a7a9cc t4 :
> 0000000000000068
> [  132.120371]  t5 : 0000000052d19905 t6 : 0000000000d19905
> [  132.125686] status: 0000000200004020 badaddr: ffffffac2b2a2928
> cause: 000000000000000d
> [  132.145321] audit: type=1701 audit(1671220069.747:12):
> auid=4294967295 uid=995 gid=994 ses=4294967295 pid=126
> comm="sd-resolve" exe="/lib/systemd/systemd-timesyncd" sig=11 res=1
> [  132.161689] systemd[1]: unhandled signal 11 code 0x1 at 0x0000006c6b6a6968
> [  132.168714] CPU: 0 PID: 1 Comm: systemd Not tainted
> 6.1.0-11009-gf4e9a8cdc25b #167
> [  132.176293] Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT)
> [  132.182906] epc : 0000006c6b6a6968 ra : 0000003f838630b2 sp :
> 0000003fe5aace60
> [  132.190125]  gp : 0000002ad234ad28 tp : 0000003f83628e70 t0 :
> 0000000000a9919e
> [  132.197357]  t1 : 0000003f838595fc t2 : 0000000000000000 s0 :
> 0000003fe5aad050
> [  132.204574]  s1 : 0000000000000000 a0 : 0000003fe5aace70 a1 :
> 0000003fe5aad058
> [  132.211791]  a2 : 0000000000000080 a3 : 0000000000000010 a4 :
> 0000000000000001
> [  132.219007]  a5 : 0000003f839a1784 a6 : 0000000000000000 a7 :
> 0000000000000000
> [  132.226223]  s2 : 0000000000000011 s3 : 000000000000000b s4 :
> 0000000000000006
> [  132.233439]  s5 : 0000000000000002 s6 : 0000003f83a85918 s7 :
> 0000000000001000
> [  132.240655]  s8 : 0000003fe5aad750 s9 : 0000003fe5aad9e0 s10:
> 0000002ad22fdd60
> [  132.247872]  s11: 2f2e2d2c2b2a2928 t3 : 6f6e6d6c6b6a6968 t4 :
> 0000000000000068
> [  132.255088]  t5 : 0000000052d19905 t6 : 0000000000d19905
> [  132.260403] status: 0000000200004020 badaddr: 0000006c6b6a6968
> cause: 000000000000000c
> [  132.269759] systemd[1]: unhandled signal 11 code 0x1 at 0x0000006c6b6a6968
> [  132.276708] CPU: 0 PID: 1 Comm: systemd Not tainted
> 6.1.0-11009-gf4e9a8cdc25b #167
> [  132.284283] Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT)
> [  132.290895] epc : 0000006c6b6a6968 ra : 0000003f838630b2 sp :
> 0000003fe5aac750
> [  132.298113]  gp : 0000002ad234ad28 tp : 0000003f83628e70 t0 :
> 0000000000a9919e
> [  132.305363]  t1 : 0000003f838595fc t2 : 0000000000000000 s0 :
> 0000003fe5aac940
> [  132.312580]  s1 : 0000000000000000 a0 : 0000003fe5aac760 a1 :
> 0000003fe5aac948
> [  132.319796]  a2 : 0000000000000080 a3 : 0000000000000010 a4 :
> 0000000000000001
> [  132.327013]  a5 : 0000003f839a1784 a6 : 0000000000000000 a7 :
> 0000000000000000
> [  132.334229]  s2 : 0000000000000011 s3 : 000000000000000b s4 :
> 0000000000000006
> [  132.341444]  s5 : 0000000000000002 s6 : 0000003f83a85918 s7 :
> 0000000000001000
> [  132.348660]  s8 : 0000003fe5aad750 s9 : 0000003fe5aad9e0 s10:
> 0000002ad22fdd60
> [  132.355877]  s11: 2f2e2d2c2b2a2928 t3 : 6f6e6d6c6b6a6968 t4 :
> 0000000000000068
> [  132.363093]  t5 : 0000000052d19905 t6 : 0000000000d19905
> [  132.368408] status: 0000000200004020 badaddr: 0000006c6b6a6968
> cause: 000000000000000c
> [  132.377123] systemd[1]: unhandled signal 11 code 0x1 at 0x0000006c6b6a6968
> [  132.384078] CPU: 0 PID: 1 Comm: systemd Not tainted
> 6.1.0-11009-gf4e9a8cdc25b #167
> [  132.391652] Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT)
> [  132.398262] epc : 0000006c6b6a6968 ra : 0000003f838630b2 sp :
> 0000003fe5aac040
> [  132.405479]  gp : 0000002ad234ad28 tp : 0000003f83628e70 t0 :
> 0000000000a9919e
> [  132.412745]  t1 : 0000003f838595fc t2 : 0000000000000000 s0 :
> 0000003fe5aac230
> [  132.419967]  s1 : 0000000000000000 a0 : 0000003fe5aac050 a1 :
> 0000003fe5aac238
> [  132.427184]  a2 : 0000000000000080 a3 : 0000000000000010 a4 :
> 0000000000000001
> [  132.434401]  a5 : 0000003f839a1784 a6 : 0000000000000000 a7 :
> 0000000000000000
> [  132.441618]  s2 : 0000000000000011 s3 : 000000000000000b s4 :
> 0000000000000006
> [  132.448833]  s5 : 0000000000000002 s6 : 0000003f83a85918 s7 :
> 0000000000001000
> [  132.456049]  s8 : 0000003fe5aad750 s9 : 0000003fe5aad9e0 s10:
> 0000002ad22fdd60
> [  132.463265]  s11: 2f2e2d2c2b2a2928 t3 : 6f6e6d6c6b6a6968 t4 :
> 0000000000000068
> [  132.470480]  t5 : 0000000052d19905 t6 : 0000000000d19905
> [  132.475804] status: 0000000200004020 badaddr: 0000006c6b6a6968
> cause: 000000000000000c
> [  132.496855] systemd[1]: unhandled signal 11 code 0x1 at 0x0000006c6b6a6968
> [  132.503842] CPU: 0 PID: 1 Comm: systemd Not tainted
> 6.1.0-11009-gf4e9a8cdc25b #167
> [  132.511415] Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT)
> [  132.518027] epc : 0000006c6b6a6968 ra : 0000003f838630b2 sp :
> 0000003fe5aab930
> [  132.525244]  gp : 0000002ad234ad28 tp : 0000003f83628e70 t0 :
> 0000000000a9919e
> [  132.532462]  t1 : 0000003f838595fc t2 : 0000000000000000 s0 :
> 0000003fe5aabb20
> [  132.539678]  s1 : 0000000000000000 a0 : 0000003fe5aab940 a1 :
> 0000003fe5aabb28
> [  132.546939]  a2 : 0000000000000080 a3 : 0000000000000010 a4 :
> 0000000000000001
> [  132.554161]  a5 : 0000003f839a1784 a6 : 0000000000000000 a7 :
> 0000000000000000
> [  132.561378]  s2 : 0000000000000011 s3 : 000000000000000b s4 :
> 0000000000000006
> [  132.568595]  s5 : 0000000000000002 s6 : 0000003f83a85918 s7 :
> 0000000000001000
> [  132.575812]  s8 : 0000003fe5aad750 s9 : 0000003fe5aad9e0 s10:
> 0000002ad22fdd60
> [  132.583029]  s11: 2f2e2d2c2b2a2928 t3 : 6f6e6d6c6b6a6968 t4 :
> 0000000000000068
> [  132.590246]  t5 : 0000000052d19905 t6 : 0000000000d19905
> [  132.595561] status: 0000000200004020 badaddr: 0000006c6b6a6968
> cause: 000000000000000c
> [  132.604448] systemd[1]: unhandled signal 11 code 0x1 at 0x0000006c6b6a6968
> [  132.611424] CPU: 0 PID: 1 Comm: systemd Not tainted
> 6.1.0-11009-gf4e9a8cdc25b #167
> [  132.618987] Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT)
> [  132.625606] epc : 0000006c6b6a6968 ra : 0000003f838630b2 sp :
> 0000003fe5aab220
> [  132.632818]  gp : 0000002ad234ad28 tp : 0000003f83628e70 t0 :
> 0000000000a9919e
> [  132.640035]  t1 : 0000003f838595fc t2 : 0000000000000000 s0 :
> 0000003fe5aab410
> [  132.647252]  s1 : 0000000000000000 a0 : 0000003fe5aab230 a1 :
> 0000003fe5aab418
> [  132.654467]  a2 : 0000000000000080 a3 : 0000000000000010 a4 :
> 0000000000000001
> [  132.661682]  a5 : 0000003f839a1784 a6 : 0000000000000000 a7 :
> 0000000000000000
> [  132.668898]  s2 : 0000000000000011 s3 : 000000000000000b s4 :
> 0000000000000006
> [  132.676113]  s5 : 0000000000000002 s6 : 0000003f83a85918 s7 :
> 0000000000001000
> [  132.683329]  s8 : 0000003fe5aad750 s9 : 0000003fe5aad9e0 s10:
> 0000002ad22fdd60
> [  132.690556]  s11: 2f2e2d2c2b2a2928 t3 : 6f6e6d6c6b6a6968 t4 :
> 0000000000000068
> [  132.697773]  t5 : 0000000052d19905 t6 : 0000000000d19905
> [  132.703086] status: 0000000200004020 badaddr: 0000006c6b6a6968
> cause: 000000000000000c
> [  132.993558] Kernel panic - not syncing: Attempted to kill init!
> exitcode=0x0000000b
> [  133.001210] CPU: 0 PID: 1 Comm: systemd Not tainted
> 6.1.0-11009-gf4e9a8cdc25b #167
> [  133.008752] Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT)
> [  133.015338] Call Trace:
> [  133.017778] [<ffffffff800055cc>] dump_backtrace+0x1c/0x24
> [  133.023174] [<ffffffff80776836>] show_stack+0x2c/0x38
> [  133.028214] [<ffffffff80780244>] dump_stack_lvl+0x3c/0x54
> [  133.033597] [<ffffffff80780270>] dump_stack+0x14/0x1c
> [  133.038633] [<ffffffff80776c00>] panic+0x102/0x29a
> [  133.043409] [<ffffffff800137ba>] do_exit+0x704/0x70a
> [  133.048362] [<ffffffff8001390e>] do_group_exit+0x24/0x70
> [  133.053659] [<ffffffff8001de54>] get_signal+0x68a/0x6dc
> [  133.058874] [<ffffffff8000494e>] do_work_pending+0xd6/0x44e
> [  133.064427] [<ffffffff800036c2>] resume_userspace_slow+0x8/0xa
> [  133.070249] ---[ end Kernel panic - not syncing: Attempted to kill
> init! exitcode=0x0000000b ]---
> 
> If I revert this patch [0] bonnie++ works as expected.
> 
> Any pointers on what could be the issue here?
> 
> [0] https://git.kernel.org/pub/scm/linux/kernel/git/palmer/linux.git/commit/?h=for-next&id=4bd1d80efb5af640f99157f39b50fb11326ce641
> 
> Cheers,
> Prabhakar

Good catch. Thanks for reporting ! Discussion around the issue and
possible ways to fix it can be found in the following email thread:

https://lore.kernel.org/linux-riscv/20221111075902.798571-1-guoren@kernel.org/

Could you please apply the patch from Guo Ren instead of [0] and check
if you have any issues with your test ? Besides, could you please share
your kernel configuration and the actual bonnie++ params from emmc_t_002.sh script ?

Regards,
Sergey