SCMI transports for Linux proposal #1
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The SCMI specification is fairly independent of the transport protocol, which can be a simple mailbox (already implemented) or anything else. The current Linux implementation however is very much dependent on the mailbox transport layer. This patch makes the SCMI core code (driver.c) independent of the mailbox transport layer and moves all mailbox related code to a new file: mailbox.c. We can now implement more transport protocols to transport SCMI messages. The transport protocols just need to provide struct scmi_transport_ops, with its version of the callbacks to enable exchange of SCMI messages. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Add missing header guards to local common.h. Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
SMT is the propotocol used to synchronize messages in shared memory buffer using a 28 byte header at shared memory base address. Exchange message payload is located right next to the header payload. SCMI mailbox transport channels use the SMT protocol to carry SCMI meta data and message synchronization data. Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
Change mailbox driver in SCMI firmware interface to use the factorized SMT driver for messages synchronization in memory buffers shared by SCMI agent and the server. Signed-off-by: Etienne Carriere <etienne.carriere@st.com>
Add a new transport channel to the SCMI firmware interface driver. The transport is called smc_func_id since it uses the SMC instruction function identifier carried by a SMC instruction as defined in SMCCC specification [1]. The function ID to be used for a given channel is defined by the the DTS property "arm,func-id". The channel expects a shared memory buffer provided by property "shmem". The smc_func_id transport uses a SMT header in shared memory buffer to manage SCMI message exchanges.
Add a new transport channel to the SCMI firmware interface driver. The OP-TEE transport channel leverage OP-TEE secure threaded context to request processing of a SCMI message. The current proposal uses a statically defined physical memory area to be used as shared memory SCMI endpoints. The location is extracted from the FDT upon property "shmem". Entry in OP-TEE threaded context is realized by invoking a service PTA (Pseudo TA) in OP-TEE OS. Each invocation carries a agent numerical identifier for which a message is pending in the shared memory. The OP-TEE service provides means to get the agent identifier value for a given shared memory location. Signed-off-by: Etienne Carriere <etienne.carriere@st.com>
Prior this change was SCMI transfer subject to timeout detection if the executing thread is rescheduled between ktime_get() call and ktime_before(ktime_get(), ...) in scmi_do_xfer(). This change tests polling return value rather than time measurement to check against timeout once exited from the polling loop. At this point, a negative poll means a timeout case. Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
Positive error codes return by the send_message() handler of a transport channel are error case and shall abort the SCMI transfer. This change makes all non-zero value returned by the handler reported to the caller as error number. Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
SCMI transport channel handler mark_txdone() is called once transmit and reponse are completed for a channel. Some transport may have nothing to do at this stage hence make the handler optional [note: if some are mandatory, init should check compliance] Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
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superseded by #2. |
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Use per_cpu_ptr_to_phys() instead of virt_to_phys() for per-cpu address conversion. In xen_starting_cpu(), per-cpu xen_vcpu_info address is converted to gfn by virt_to_gfn() macro. However, since the virt_to_gfn(v) assumes the given virtual address is in linear mapped kernel memory area, it can not convert the per-cpu memory if it is allocated on vmalloc area. This depends on CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK. If it is enabled, the first chunk of percpu memory is linear mapped. In the other case, that is allocated from vmalloc area. Moreover, if the first chunk of percpu has run out until allocating xen_vcpu_info, it will be allocated on the 2nd chunk, which is based on kernel memory or vmalloc memory (depends on CONFIG_NEED_PER_CPU_KM). Without this fix and kernel configured to use vmalloc area for the percpu memory, the Dom0 kernel will fail to boot with following errors. [ 0.466172] Xen: initializing cpu0 [ 0.469601] ------------[ cut here ]------------ [ 0.474295] WARNING: CPU: 0 PID: 1 at arch/arm64/xen/../../arm/xen/enlighten.c:153 xen_starting_cpu+0x160/0x180 [ 0.484435] Modules linked in: [ 0.487565] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.9.0-rc4+ linaro-swg#4 [ 0.493895] Hardware name: Socionext Developer Box (DT) [ 0.499194] pstate: 00000005 (nzcv daif -PAN -UAO BTYPE=--) [ 0.504836] pc : xen_starting_cpu+0x160/0x180 [ 0.509263] lr : xen_starting_cpu+0xb0/0x180 [ 0.513599] sp : ffff8000116cbb60 [ 0.516984] x29: ffff8000116cbb60 x28: ffff80000abec000 [ 0.522366] x27: 0000000000000000 x26: 0000000000000000 [ 0.527754] x25: ffff80001156c000 x24: fffffdffbfcdb600 [ 0.533129] x23: 0000000000000000 x22: 0000000000000000 [ 0.538511] x21: ffff8000113a99c8 x20: ffff800010fe4f68 [ 0.543892] x19: ffff8000113a9988 x18: 0000000000000010 [ 0.549274] x17: 0000000094fe0f81 x16: 00000000deadbeef [ 0.554655] x15: ffffffffffffffff x14: 0720072007200720 [ 0.560037] x13: 0720072007200720 x12: 0720072007200720 [ 0.565418] x11: 0720072007200720 x10: 0720072007200720 [ 0.570801] x9 : ffff8000100fbdc0 x8 : ffff800010715208 [ 0.576182] x7 : 0000000000000054 x6 : ffff00001b790f00 [ 0.581564] x5 : ffff800010bbf880 x4 : 0000000000000000 [ 0.586945] x3 : 0000000000000000 x2 : ffff80000abec000 [ 0.592327] x1 : 000000000000002f x0 : 0000800000000000 [ 0.597716] Call trace: [ 0.600232] xen_starting_cpu+0x160/0x180 [ 0.604309] cpuhp_invoke_callback+0xac/0x640 [ 0.608736] cpuhp_issue_call+0xf4/0x150 [ 0.612728] __cpuhp_setup_state_cpuslocked+0x128/0x2c8 [ 0.618030] __cpuhp_setup_state+0x84/0xf8 [ 0.622192] xen_guest_init+0x324/0x364 [ 0.626097] do_one_initcall+0x54/0x250 [ 0.630003] kernel_init_freeable+0x12c/0x2c8 [ 0.634428] kernel_init+0x1c/0x128 [ 0.637988] ret_from_fork+0x10/0x18 [ 0.641635] ---[ end trace d95b5309a33f8b27 ]--- [ 0.646337] ------------[ cut here ]------------ [ 0.651005] kernel BUG at arch/arm64/xen/../../arm/xen/enlighten.c:158! [ 0.657697] Internal error: Oops - BUG: 0 [#1] SMP [ 0.662548] Modules linked in: [ 0.665676] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 5.9.0-rc4+ linaro-swg#4 [ 0.673398] Hardware name: Socionext Developer Box (DT) [ 0.678695] pstate: 00000005 (nzcv daif -PAN -UAO BTYPE=--) [ 0.684338] pc : xen_starting_cpu+0x178/0x180 [ 0.688765] lr : xen_starting_cpu+0x144/0x180 [ 0.693188] sp : ffff8000116cbb60 [ 0.696573] x29: ffff8000116cbb60 x28: ffff80000abec000 [ 0.701955] x27: 0000000000000000 x26: 0000000000000000 [ 0.707344] x25: ffff80001156c000 x24: fffffdffbfcdb600 [ 0.712718] x23: 0000000000000000 x22: 0000000000000000 [ 0.718107] x21: ffff8000113a99c8 x20: ffff800010fe4f68 [ 0.723481] x19: ffff8000113a9988 x18: 0000000000000010 [ 0.728863] x17: 0000000094fe0f81 x16: 00000000deadbeef [ 0.734245] x15: ffffffffffffffff x14: 0720072007200720 [ 0.739626] x13: 0720072007200720 x12: 0720072007200720 [ 0.745008] x11: 0720072007200720 x10: 0720072007200720 [ 0.750390] x9 : ffff8000100fbdc0 x8 : ffff800010715208 [ 0.755771] x7 : 0000000000000054 x6 : ffff00001b790f00 [ 0.761153] x5 : ffff800010bbf880 x4 : 0000000000000000 [ 0.766534] x3 : 0000000000000000 x2 : 00000000deadbeef [ 0.771916] x1 : 00000000deadbeef x0 : ffffffffffffffea [ 0.777304] Call trace: [ 0.779819] xen_starting_cpu+0x178/0x180 [ 0.783898] cpuhp_invoke_callback+0xac/0x640 [ 0.788325] cpuhp_issue_call+0xf4/0x150 [ 0.792317] __cpuhp_setup_state_cpuslocked+0x128/0x2c8 [ 0.797619] __cpuhp_setup_state+0x84/0xf8 [ 0.801779] xen_guest_init+0x324/0x364 [ 0.805683] do_one_initcall+0x54/0x250 [ 0.809590] kernel_init_freeable+0x12c/0x2c8 [ 0.814016] kernel_init+0x1c/0x128 [ 0.817583] ret_from_fork+0x10/0x18 [ 0.821226] Code: d0006980 f9427c00 cb000300 17ffffea (d4210000) [ 0.827415] ---[ end trace d95b5309a33f8b28 ]--- [ 0.832076] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b [ 0.839815] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b ]--- Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/160196697165.60224.17470743378683334995.stgit@devnote2 Signed-off-by: Juergen Gross <jgross@suse.com>
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In mmc_queue_setup_discard() the mmc driver queue's discard_granularity might be set as 0 (when card->pref_erase > max_discard) while the mmc device still declares to support discard operation. This is buggy and triggered the following kernel warning message, WARNING: CPU: 0 PID: 135 at __blkdev_issue_discard+0x200/0x294 CPU: 0 PID: 135 Comm: f2fs_discard-17 Not tainted 5.9.0-rc6 #1 Hardware name: Google Kevin (DT) pstate: 00000005 (nzcv daif -PAN -UAO BTYPE=--) pc : __blkdev_issue_discard+0x200/0x294 lr : __blkdev_issue_discard+0x54/0x294 sp : ffff800011dd3b10 x29: ffff800011dd3b10 x28: 0000000000000000 x27: ffff800011dd3cc4 x26: ffff800011dd3e18 x25: 000000000004e69b x24: 0000000000000c40 x23: ffff0000f1deaaf0 x22: ffff0000f2849200 x21: 00000000002734d8 x20: 0000000000000008 x19: 0000000000000000 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 x14: 0000000000000394 x13: 0000000000000000 x12: 0000000000000000 x11: 0000000000000000 x10: 00000000000008b0 x9 : ffff800011dd3cb0 x8 : 000000000004e69b x7 : 0000000000000000 x6 : ffff0000f1926400 x5 : ffff0000f1940800 x4 : 0000000000000000 x3 : 0000000000000c40 x2 : 0000000000000008 x1 : 00000000002734d8 x0 : 0000000000000000 Call trace: __blkdev_issue_discard+0x200/0x294 __submit_discard_cmd+0x128/0x374 __issue_discard_cmd_orderly+0x188/0x244 __issue_discard_cmd+0x2e8/0x33c issue_discard_thread+0xe8/0x2f0 kthread+0x11c/0x120 ret_from_fork+0x10/0x1c ---[ end trace e4c8023d33dfe77a ]--- This patch fixes the issue by setting discard_granularity as SECTOR_SIZE instead of 0 when (card->pref_erase > max_discard) is true. Now no more complain from __blkdev_issue_discard() for the improper value of discard granularity. This issue is exposed after commit b35fd74 ("block: check queue's limits.discard_granularity in __blkdev_issue_discard()"), a "Fixes:" tag is also added for the commit to make sure people won't miss this patch after applying the change of __blkdev_issue_discard(). Fixes: e056a1b ("mmc: queue: let host controllers specify maximum discard timeout") Fixes: b35fd74 ("block: check queue's limits.discard_granularity in __blkdev_issue_discard()"). Reported-and-tested-by: Vicente Bergas <vicencb@gmail.com> Signed-off-by: Coly Li <colyli@suse.de> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Ulf Hansson <ulf.hansson@linaro.org> Link: https://lore.kernel.org/r/20201002013852.51968-1-colyli@suse.de Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
etienne-lms
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The syzbot reported the below general protection fault: general protection fault, probably for non-canonical address 0xe00eeaee0000003b: 0000 [#1] PREEMPT SMP KASAN KASAN: maybe wild-memory-access in range [0x00777770000001d8-0x00777770000001df] CPU: 1 PID: 10488 Comm: syz-executor721 Not tainted 5.9.0-rc3-syzkaller #0 RIP: 0010:unlink_file_vma+0x57/0xb0 mm/mmap.c:164 Call Trace: free_pgtables+0x1b3/0x2f0 mm/memory.c:415 exit_mmap+0x2c0/0x530 mm/mmap.c:3184 __mmput+0x122/0x470 kernel/fork.c:1076 mmput+0x53/0x60 kernel/fork.c:1097 exit_mm kernel/exit.c:483 [inline] do_exit+0xa8b/0x29f0 kernel/exit.c:793 do_group_exit+0x125/0x310 kernel/exit.c:903 get_signal+0x428/0x1f00 kernel/signal.c:2757 arch_do_signal+0x82/0x2520 arch/x86/kernel/signal.c:811 exit_to_user_mode_loop kernel/entry/common.c:136 [inline] exit_to_user_mode_prepare+0x1ae/0x200 kernel/entry/common.c:167 syscall_exit_to_user_mode+0x7e/0x2e0 kernel/entry/common.c:242 entry_SYSCALL_64_after_hwframe+0x44/0xa9 It's because the ->mmap() callback can change vma->vm_file and fput the original file. But the commit d70cec8 ("mm: mmap: merge vma after call_mmap() if possible") failed to catch this case and always fput() the original file, hence add an extra fput(). [ Thanks Hillf for pointing this extra fput() out. ] Fixes: d70cec8 ("mm: mmap: merge vma after call_mmap() if possible") Reported-by: syzbot+c5d5a51dcbb558ca0cb5@syzkaller.appspotmail.com Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Christian König <ckoenig.leichtzumerken@gmail.com> Cc: Hongxiang Lou <louhongxiang@huawei.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Dave Airlie <airlied@redhat.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: John Hubbard <jhubbard@nvidia.com> Link: https://lkml.kernel.org/r/20200916090733.31427-1-linmiaohe@huawei.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Proposal for 2 added transport channels for the SCMI driver:
This is based on Viresh https://lkml.org/lkml/2020/1/28/207, as 1st commit in the series.