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2026-04-17ipmi:ssif: Clean up kthread on errorsCorey Minyard-1/+12
If an error occurs after the ssif kthread is created, but before the main IPMI code starts the ssif interface, the ssif kthread will not be stopped. So make sure the kthread is stopped on an error condition if it is running. Fixes: 259307074bfc ("ipmi: Add SMBus interface driver (SSIF)") Reported-by: Li Xiao <<252270051@hdu.edu.cn> Cc: stable@vger.kernel.org Reviewed-by: Li Xiao <252270051@hdu.edu.cn> Signed-off-by: Corey Minyard <corey@minyard.net>
2026-04-13ipmi:ssif: Remove unnecessary indentionCorey Minyard-16/+12
A section was in {} that didn't need to be, move the variable definition to the top and set th eindentino properly. Signed-off-by: Corey Minyard <corey@minyard.net>
2026-04-07ipmi: ssif_bmc: Fix KUnit test link failure when KUNIT=mJian Zhang-1/+1
Building with CONFIG_KUNIT=m and CONFIG_SSIF_IPMI_BMC_KUNIT_TEST=y results in link errors such as: undefined reference to `kunit_binary_assert_format' undefined reference to `__kunit_do_failed_assertion' This happens because the test code is built-in while the KUnit core is built as a module, so the required KUnit symbols are not available at link time. Fix this by requiring KUNIT to be built-in when enabling SSIF_IPMI_BMC_KUNIT_TEST. Signed-off-by: Jian Zhang <zhangjian.3032@bytedance.com> Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202604071448.zUBjPYPu-lkp@intel.com/ Message-ID: <20260407094647.356661-1-zhangjian.3032@bytedance.com> Signed-off-by: Corey Minyard <corey@minyard.net>
2026-04-03ipmi: ssif_bmc: add unit test for state machineJian Zhang-0/+380
Add some unit test for state machine when in SSIF_ABORTING state. Fixes: dd2bc5cc9e25 ("ipmi: ssif_bmc: Add SSIF BMC driver") Signed-off-by: Jian Zhang <zhangjian.3032@bytedance.com> Message-ID: <20260403143939.434017-1-zhangjian.3032@bytedance.com> Signed-off-by: Corey Minyard <corey@minyard.net>
2026-04-03ipmi: ssif_bmc: change log level to dbg in irq callbackJian Zhang-9/+9
Long-running tests indicate that this logging can occasionally disrupt timing and lead to request/response corruption. Irq handler need to be executed as fast as possible, most I2C slave IRQ implementations are byte-level, logging here can significantly affect transfer behavior and timing. It is recommended to use dev_dbg() for these messages. Fixes: dd2bc5cc9e25 ("ipmi: ssif_bmc: Add SSIF BMC driver") Signed-off-by: Jian Zhang <zhangjian.3032@bytedance.com> Message-ID: <20260403090603.3988423-4-zhangjian.3032@bytedance.com> Signed-off-by: Corey Minyard <corey@minyard.net>
2026-04-03ipmi: ssif_bmc: fix message desynchronization after truncated responseJian Zhang-0/+14
A truncated response, caused by host power-off, or other conditions, can lead to message desynchronization. Raw trace data (STOP loss scenario, add state transition comment): 1. T-1: Read response phase (SSIF_RES_SENDING) 8271.955342 WR_RCV [03] <- Read polling cmd 8271.955348 RD_REQ [04] <== SSIF_RES_SENDING <- start sending response 8271.955436 RD_PRO [b4] 8271.955527 RD_PRO [00] 8271.955618 RD_PRO [c1] 8271.955707 RD_PRO [00] 8271.955814 RD_PRO [ad] <== SSIF_RES_SENDING <- last byte <- !! STOP lost (truncated response) 2. T: New Write request arrives, BMC still in SSIF_RES_SENDING 8271.967973 WR_REQ [] <== SSIF_RES_SENDING >> SSIF_ABORTING <- log: unexpected WR_REQ in RES_SENDING 8271.968447 WR_RCV [02] <== SSIF_ABORTING <- do nothing 8271.968452 WR_RCV [02] <== SSIF_ABORTING <- do nothing 8271.968454 WR_RCV [18] <== SSIF_ABORTING <- do nothing 8271.968456 WR_RCV [01] <== SSIF_ABORTING <- do nothing 8271.968458 WR_RCV [66] <== SSIF_ABORTING <- do nothing 8271.978714 STOP [] <== SSIF_ABORTING >> SSIF_READY <- log: unexpected SLAVE STOP in state=SSIF_ABORTING 3. T+1: Next Read polling, treated as a fresh transaction 8271.979125 WR_REQ [] <== SSIF_READY >> SSIF_START 8271.979326 WR_RCV [03] <== SSIF_START >> SSIF_SMBUS_CMD <- smbus_cmd=0x03 8271.979331 RD_REQ [04] <== SSIF_RES_SENDING <- sending response 8271.979427 RD_PRO [b4] <- !! this is T's stale response -> desynchronization When in SSIF_ABORTING state, a newly arrived command should still be handled to avoid dropping the request or causing message desynchronization. Fixes: dd2bc5cc9e25 ("ipmi: ssif_bmc: Add SSIF BMC driver") Signed-off-by: Jian Zhang <zhangjian.3032@bytedance.com> Message-ID: <20260403090603.3988423-3-zhangjian.3032@bytedance.com> Signed-off-by: Corey Minyard <corey@minyard.net>
2026-04-03ipmi: ssif_bmc: fix missing check for copy_to_user() partial failureJian Zhang-0/+2
copy_to_user() returns the number of bytes that could not be copied, with a non-zero value indicating a partial or complete failure. The current code only checks for negative return values and treats all non-negative results as success. Treating any positive return value from copy_to_user() as an error and returning -EFAULT. Fixes: dd2bc5cc9e25 ("ipmi: ssif_bmc: Add SSIF BMC driver") Signed-off-by: Jian Zhang <zhangjian.3032@bytedance.com> Message-ID: <20260403090603.3988423-2-zhangjian.3032@bytedance.com> Signed-off-by: Corey Minyard <corey@minyard.net>
2026-04-03ipmi: ssif_bmc: cancel response timer on removeJian Zhang-0/+1
The response timer can stay armed across device teardown. If it fires after remove, the callback dereferences the SSIF context and the i2c client after teardown has started. Cancel the timer in remove so the callback cannot run after the device is unregistered. Signed-off-by: Jian Zhang <zhangjian.3032@bytedance.com> Message-ID: <20260403090603.3988423-1-zhangjian.3032@bytedance.com> Signed-off-by: Corey Minyard <corey@minyard.net>
2026-03-05ipmi: Replace use of system_wq with system_percpu_wqMarco Crivellari-5/+5
This patch continues the effort to refactor workqueue APIs, which has begun with the changes introducing new workqueues and a new alloc_workqueue flag: commit 128ea9f6ccfb ("workqueue: Add system_percpu_wq and system_dfl_wq") commit 930c2ea566af ("workqueue: Add new WQ_PERCPU flag") The point of the refactoring is to eventually alter the default behavior of workqueues to become unbound by default so that their workload placement is optimized by the scheduler. Before that to happen after a careful review and conversion of each individual case, workqueue users must be converted to the better named new workqueues with no intended behaviour changes: system_wq -> system_percpu_wq system_unbound_wq -> system_dfl_wq This way the old obsolete workqueues (system_wq, system_unbound_wq) can be removed in the future. Suggested-by: Tejun Heo <tj@kernel.org> Signed-off-by: Marco Crivellari <marco.crivellari@suse.com> Message-ID: <20251224161301.135382-1-marco.crivellari@suse.com> Signed-off-by: Corey Minyard <corey@minyard.net>
2026-02-26Merge tag 'for-linus-7.0-1' of https://github.com/cminyard/linux-ipmiLinus Torvalds-60/+125
Pull IPMI driver fixes from Corey Minyard: "This mostly revolves around getting the driver to behave when the IPMI device misbehaves. Past attempts have not worked very well because I didn't have hardware I could make do this, and AI was fairly useless for help on this. So I modified qemu and my test suite so I could reproduce a misbehaving IPMI device, and with that I was able to fix the issues" * tag 'for-linus-7.0-1' of https://github.com/cminyard/linux-ipmi: ipmi:si: Fix check for a misbehaving BMC ipmi:msghandler: Handle error returns from the SMI sender ipmi:si: Don't block module unload if the BMC is messed up ipmi:si: Use a long timeout when the BMC is misbehaving ipmi:si: Handle waiting messages when BMC failure detected ipmi:ls2k: Make ipmi_ls2k_platform_driver static ipmi: ipmb: initialise event handler read bytes ipmi: Consolidate the run to completion checking for xmit msgs lock ipmi: Fix use-after-free and list corruption on sender error
2026-02-23ipmi:si: Fix check for a misbehaving BMCCorey Minyard-11/+13
There is a race on checking the state in the sender, it needs to be checked under a lock. But you also need a check to avoid issues with a misbehaving BMC for run to completion mode. So leave the check at the beginning for run to completion, and add a check under the lock to avoid the race. Reported-by: Rafael J. Wysocki <rafael@kernel.org> Fixes: bc3a9d217755 ("ipmi:si: Gracefully handle if the BMC is non-functional") Cc: stable@vger.kernel.org # 4.18 Signed-off-by: Corey Minyard <corey@minyard.net> Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
2026-02-23ipmi:msghandler: Handle error returns from the SMI senderCorey Minyard-32/+68
It used to be, until recently, that the sender operation on the low level interfaces would not fail. That's not the case any more with recent changes. So check the return value from the sender operation, and propagate it back up from there and handle the errors in all places. Reported-by: Rafael J. Wysocki <rafael@kernel.org> Fixes: bc3a9d217755 ("ipmi:si: Gracefully handle if the BMC is non-functional") Cc: stable@vger.kernel.org # 4.18 Signed-off-by: Corey Minyard <corey@minyard.net> Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
2026-02-23ipmi:si: Don't block module unload if the BMC is messed upCorey Minyard-1/+2
If the BMC is in a bad state, don't bother waiting for queues messages since there can't be any. Otherwise the unload is blocked until the BMC is back in a good state. Reported-by: Rafael J. Wysocki <rafael@kernel.org> Fixes: bc3a9d217755 ("ipmi:si: Gracefully handle if the BMC is non-functional") Cc: stable@vger.kernel.org # 4.18 Signed-off-by: Corey Minyard <corey@minyard.net> Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
2026-02-21Convert 'alloc_obj' family to use the new default GFP_KERNEL argumentLinus Torvalds-13/+13
This was done entirely with mindless brute force, using git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' | xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/' to convert the new alloc_obj() users that had a simple GFP_KERNEL argument to just drop that argument. Note that due to the extreme simplicity of the scripting, any slightly more complex cases spread over multiple lines would not be triggered: they definitely exist, but this covers the vast bulk of the cases, and the resulting diff is also then easier to check automatically. For the same reason the 'flex' versions will be done as a separate conversion. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21treewide: Replace kmalloc with kmalloc_obj for non-scalar typesKees Cook-18/+16
This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-06ipmi:si: Use a long timeout when the BMC is misbehavingCorey Minyard-1/+3
If the driver goes into HOSED state, don't reset the timeout to the short timeout in the timeout handler. Reported-by: Igor Raits <igor@gooddata.com> Closes: https://lore.kernel.org/linux-acpi/CAK8fFZ58fidGUCHi5WFX0uoTPzveUUDzT=k=AAm4yWo3bAuCFg@mail.gmail.com/ Fixes: bc3a9d217755 ("ipmi:si: Gracefully handle if the BMC is non-functional") Cc: stable@vger.kernel.org # 4.18 Signed-off-by: Corey Minyard <corey@minyard.net>
2026-02-06ipmi:si: Handle waiting messages when BMC failure detectedCorey Minyard-0/+6
If a BMC failure is detected, the current message is returned with an error. However, if there was a waiting message, it would not be handled. Add a check for the waiting message after handling the current message. Suggested-by: Guenter Roeck <linux@roeck-us.net> Reported-by: Rafael J. Wysocki <rafael@kernel.org> Closes: https://lore.kernel.org/linux-acpi/CAK8fFZ58fidGUCHi5WFX0uoTPzveUUDzT=k=AAm4yWo3bAuCFg@mail.gmail.com/ Fixes: bc3a9d217755 ("ipmi:si: Gracefully handle if the BMC is non-functional") Cc: stable@vger.kernel.org # 4.18 Signed-off-by: Corey Minyard <corey@minyard.net>
2026-02-03ipmi:ls2k: Make ipmi_ls2k_platform_driver staticCorey Minyard-1/+1
No need for it to be global. Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202601170753.3zDBerGP-lkp@intel.com/ Signed-off-by: Corey Minyard <corey@minyard.net>
2026-02-03ipmi: ipmb: initialise event handler read bytesMatt Johnston-0/+5
IPMB doesn't use i2c reads, but the handler needs to set a value. Otherwise an i2c read will return an uninitialised value from the bus driver. Fixes: 63c4eb347164 ("ipmi:ipmb: Add initial support for IPMI over IPMB") Signed-off-by: Matt Johnston <matt@codeconstruct.com.au> Message-ID: <20260113-ipmb-read-init-v1-1-a9cbce7b94e3@codeconstruct.com.au> Signed-off-by: Corey Minyard <corey@minyard.net>
2026-02-03ipmi: Consolidate the run to completion checking for xmit msgs lockCorey Minyard-18/+24
It made things hard to read, move the check to a function. Signed-off-by: Corey Minyard <corey@minyard.net> Reviewed-by: Breno Leitao <leitao@debian.org>
2026-02-03ipmi: Fix use-after-free and list corruption on sender errorCorey Minyard-2/+9
The analysis from Breno: When the SMI sender returns an error, smi_work() delivers an error response but then jumps back to restart without cleaning up properly: 1. intf->curr_msg is not cleared, so no new message is pulled 2. newmsg still points to the message, causing sender() to be called again with the same message 3. If sender() fails again, deliver_err_response() is called with the same recv_msg that was already queued for delivery This causes list_add corruption ("list_add double add") because the recv_msg is added to the user_msgs list twice. Subsequently, the corrupted list leads to use-after-free when the memory is freed and reused, and eventually a NULL pointer dereference when accessing recv_msg->done. The buggy sequence: sender() fails -> deliver_err_response(recv_msg) // recv_msg queued for delivery -> goto restart // curr_msg not cleared! sender() fails again (same message!) -> deliver_err_response(recv_msg) // tries to queue same recv_msg -> LIST CORRUPTION Fix this by freeing the message and setting it to NULL on a send error. Also, always free the newmsg on a send error, otherwise it will leak. Reported-by: Breno Leitao <leitao@debian.org> Closes: https://lore.kernel.org/lkml/20260127-ipmi-v1-0-ba5cc90f516f@debian.org/ Fixes: 9cf93a8fa9513 ("ipmi: Allow an SMI sender to return an error") Cc: stable@vger.kernel.org # 4.18 Reviewed-by: Breno Leitao <leitao@debian.org> Signed-off-by: Corey Minyard <corey@minyard.net>
2025-12-05Merge tag 'for-linus-6.19-1' of https://github.com/cminyard/linux-ipmiLinus Torvalds-7/+17
Pull IPMI updates from Corey Minyard: "Minor IPMI fixes: - Some device tree cleanups and a maintainer add - Fix a race when handling channel updates that could result in errors being reported to the user in some cases" * tag 'for-linus-6.19-1' of https://github.com/cminyard/linux-ipmi: MAINTAINERS: Add entry on Loongson-2K IPMI driver dt-bindings: ipmi: Convert aspeed,ast2400-ibt-bmc to DT schema dt-bindings: ipmi: Convert nuvoton,npcm750-kcs-bmc to DT schema ipmi: Skip channel scan if channels are already marked ready ipmi: Fix __scan_channels() failing to rescan channels ipmi: Fix the race between __scan_channels() and deliver_response()
2025-12-03Merge tag 'printk-for-6.19' of ↵Linus Torvalds-6/+3
git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux Pull printk updates from Petr Mladek: - Allow creaing nbcon console drivers with an unsafe write_atomic() callback that can only be called by the final nbcon_atomic_flush_unsafe(). Otherwise, the driver would rely on the kthread. It is going to be used as the-best-effort approach for an experimental nbcon netconsole driver, see https://lore.kernel.org/r/20251121-nbcon-v1-2-503d17b2b4af@debian.org Note that a safe .write_atomic() callback is supposed to work in NMI context. But some networking drivers are not safe even in IRQ context: https://lore.kernel.org/r/oc46gdpmmlly5o44obvmoatfqo5bhpgv7pabpvb6sjuqioymcg@gjsma3ghoz35 In an ideal world, all networking drivers would be fixed first and the atomic flush would be blocked only in NMI context. But it brings the question how reliable networking drivers are when the system is in a bad state. They might block flushing more reliable serial consoles which are more suitable for serious debugging anyway. - Allow to use the last 4 bytes of the printk ring buffer. - Prevent queuing IRQ work and block printk kthreads when consoles are suspended. Otherwise, they create non-necessary churn or even block the suspend. - Release console_lock() between each record in the kthread used for legacy consoles on RT. It might significantly speed up the boot. - Release nbcon context between each record in the atomic flush. It prevents stalls of the related printk kthread after it has lost the ownership in the middle of a record - Add support for NBCON consoles into KDB - Add %ptsP modifier for printing struct timespec64 and use it where possible - Misc code clean up * tag 'printk-for-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: (48 commits) printk: Use console_is_usable on console_unblank arch: um: kmsg_dump: Use console_is_usable drivers: serial: kgdboc: Drop checks for CON_ENABLED and CON_BOOT lib/vsprintf: Unify FORMAT_STATE_NUM handlers printk: Avoid irq_work for printk_deferred() on suspend printk: Avoid scheduling irq_work on suspend printk: Allow printk_trigger_flush() to flush all types tracing: Switch to use %ptSp scsi: snic: Switch to use %ptSp scsi: fnic: Switch to use %ptSp s390/dasd: Switch to use %ptSp ptp: ocp: Switch to use %ptSp pps: Switch to use %ptSp PCI: epf-test: Switch to use %ptSp net: dsa: sja1105: Switch to use %ptSp mmc: mmc_test: Switch to use %ptSp media: av7110: Switch to use %ptSp ipmi: Switch to use %ptSp igb: Switch to use %ptSp e1000e: Switch to use %ptSp ...
2025-11-19ipmi: Switch to use %ptSpAndy Shevchenko-6/+3
Use %ptSp instead of open coded variants to print content of struct timespec64 in human readable format. Acked-by: Corey Minyard <cminyard@mvista.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://patch.msgid.link/20251113150217.3030010-12-andriy.shevchenko@linux.intel.com Signed-off-by: Petr Mladek <pmladek@suse.com>
2025-10-14ipmi: Skip channel scan if channels are already marked readyJinhui Guo-0/+4
Channels remain static unless the BMC firmware changes. Therefore, rescanning is unnecessary while they are marked ready and no BMC update has occurred. Signed-off-by: Jinhui Guo <guojinhui.liam@bytedance.com> Message-ID: <20250930074239.2353-4-guojinhui.liam@bytedance.com> Signed-off-by: Corey Minyard <corey@minyard.net>
2025-10-14ipmi: Fix __scan_channels() failing to rescan channelsJinhui Guo-5/+13
channel_handler() sets intf->channels_ready to true but never clears it, so __scan_channels() skips any rescan. When the BMC firmware changes a rescan is required. Allow it by clearing the flag before starting a new scan. Signed-off-by: Jinhui Guo <guojinhui.liam@bytedance.com> Message-ID: <20250930074239.2353-3-guojinhui.liam@bytedance.com> Signed-off-by: Corey Minyard <corey@minyard.net>
2025-10-14ipmi: Fix the race between __scan_channels() and deliver_response()Jinhui Guo-2/+0
The race window between __scan_channels() and deliver_response() causes the parameters of some channels to be set to 0. 1.[CPUA] __scan_channels() issues an IPMI request and waits with wait_event() until all channels have been scanned. wait_event() internally calls might_sleep(), which might yield the CPU. (Moreover, an interrupt can preempt wait_event() and force the task to yield the CPU.) 2.[CPUB] deliver_response() is invoked when the CPU receives the IPMI response. After processing a IPMI response, deliver_response() directly assigns intf->wchannels to intf->channel_list and sets intf->channels_ready to true. However, not all channels are actually ready for use. 3.[CPUA] Since intf->channels_ready is already true, wait_event() never enters __wait_event(). __scan_channels() immediately clears intf->null_user_handler and exits. 4.[CPUB] Once intf->null_user_handler is set to NULL, deliver_response() ignores further IPMI responses, leaving the remaining channels zero-initialized and unusable. CPUA CPUB ------------------------------- ----------------------------- __scan_channels() intf->null_user_handler = channel_handler; send_channel_info_cmd(intf, 0); wait_event(intf->waitq, intf->channels_ready); do { might_sleep(); deliver_response() channel_handler() intf->channel_list = intf->wchannels + set; intf->channels_ready = true; send_channel_info_cmd(intf, intf->curr_channel); if (condition) break; __wait_event(wq_head, condition); } while(0) intf->null_user_handler = NULL; deliver_response() if (!msg->user) if (intf->null_user_handler) rv = -EINVAL; return rv; ------------------------------- ----------------------------- Fix the race between __scan_channels() and deliver_response() by deferring both the assignment intf->channel_list = intf->wchannels and the flag intf->channels_ready = true until all channels have been successfully scanned or until the IPMI request has failed. Signed-off-by: Jinhui Guo <guojinhui.liam@bytedance.com> Message-ID: <20250930074239.2353-2-guojinhui.liam@bytedance.com> Signed-off-by: Corey Minyard <corey@minyard.net>
2025-10-07ipmi: Fix handling of messages with provided receive message pointerGuenter Roeck-1/+4
Prior to commit b52da4054ee0 ("ipmi: Rework user message limit handling"), i_ipmi_request() used to increase the user reference counter if the receive message is provided by the caller of IPMI API functions. This is no longer the case. However, ipmi_free_recv_msg() is still called and decreases the reference counter. This results in the reference counter reaching zero, the user data pointer is released, and all kinds of interesting crashes are seen. Fix the problem by increasing user reference counter if the receive message has been provided by the caller. Fixes: b52da4054ee0 ("ipmi: Rework user message limit handling") Reported-by: Eric Dumazet <edumazet@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Greg Thelen <gthelen@google.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Message-ID: <20251006201857.3433837-1-linux@roeck-us.net> Signed-off-by: Corey Minyard <corey@minyard.net>
2025-09-16ipmi: Add Loongson-2K BMC supportBinbin Zhou-0/+208
This patch adds Loongson-2K BMC IPMI support. According to the existing design, we use software simulation to implement the KCS interface registers: Stauts/Command/Data_Out/Data_In. Also since both host side and BMC side read and write kcs status, fifo flag is used to ensure data consistency. The single KCS message block is as follows: +-------------------------------------------------------------------------+ |FIFO flags| KCS register data | CMD data | KCS version | WR REQ | WR ACK | +-------------------------------------------------------------------------+ Co-developed-by: Chong Qiao <qiaochong@loongson.cn> Signed-off-by: Chong Qiao <qiaochong@loongson.cn> Reviewed-by: Huacai Chen <chenhuacai@loongson.cn> Acked-by: Corey Minyard <corey@minyard.net> Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn> Message-ID: <8f9ffb6f0405345af8f04193ce1510aacd075e72.1756987761.git.zhoubinbin@loongson.cn> Signed-off-by: Corey Minyard <corey@minyard.net>
2025-09-08ipmi:si: Gracefully handle if the BMC is non-functionalCorey Minyard-6/+23
If the BMC is not functional, the driver goes into an error state and starts a 1 second timer. When the timer times out, it will attempt a simple message. If the BMC interacts correctly, the driver will start accepting messages again. If not, it remains in error state. If the driver goes into error state, all messages current and pending will return with an error. This should more gracefully handle when the BMC becomes non-operational, as opposed to trying each messages individually and failing them. Signed-off-by: Corey Minyard <corey@minyard.net>
2025-09-08ipmi: Rename "user_data" to "recv_msg" in an SMI messageCorey Minyard-13/+13
It's only used to hold the corresponding receive message, so fix the name to make that clear and the type so nothing else can be accidentally assigned to it. Signed-off-by: Corey Minyard <corey@minyard.net>
2025-09-08ipmi: Allow an SMI sender to return an errorCorey Minyard-20/+29
Getting ready for handling when a BMC is non-responsive or broken, allow the sender operation to fail in an SMI. If it was a user-generated message it will return the error. The powernv code was already doing this internally, but the way it was written could result in deep stack descent if there were a lot of messages queued. Have its send return an error in this case. Signed-off-by: Corey Minyard <corey@minyard.net>
2025-09-08ipmi:si: Move flags get start to its own functionCorey Minyard-6/+13
It's about to be used from another place, and this looks better, anyway. Signed-off-by: Corey Minyard <corey@minyard.net>
2025-09-08ipmi:si: Merge some if statementsCorey Minyard-9/+5
Changes resulted in a silly looking piece of logic. Get rid of a goto and use if statements properly. Signed-off-by: Corey Minyard <corey@minyard.net>
2025-09-08ipmi: Set a timer for maintenance modeCorey Minyard-2/+6
Now that maintenance mode rejects all messages, there's nothing to run time timer. Make sure the timer is running in maintenance mode. Signed-off-by: Corey Minyard <corey@minyard.net> Tested-by: Frederick Lawler <fred@cloudflare.com>
2025-09-08ipmi: Add a maintenance mode sysfs fileCorey Minyard-0/+23
So you can see if it's in maintenance mode and see how long is left. Signed-off-by: Corey Minyard <corey@minyard.net> Tested-by: Frederick Lawler <fred@cloudflare.com>
2025-09-08ipmi: Disable sysfs access and requests in maintenance modeCorey Minyard-0/+11
If the driver goes into any maintenance mode, disable sysfs access until it is done. If the driver goes into reset maintenance mode, disable all messages until it is done. Signed-off-by: Corey Minyard <corey@minyard.net> Tested-by: Frederick Lawler <fred@cloudflare.com>
2025-09-08ipmi: Differentiate between reset and firmware update in maintenanceCorey Minyard-12/+30
This allows later changes to have different behaviour during a reset verses a firmware update. Signed-off-by: Corey Minyard <corey@minyard.net> Tested-by: Frederick Lawler <fred@cloudflare.com>
2025-09-08ipmi: Rework user message limit handlingCorey Minyard-220/+200
The limit on the number of user messages had a number of issues, improper counting in some cases and a use after free. Restructure how this is all done to handle more in the receive message allocation routine, so all refcouting and user message limit counts are done in that routine. It's a lot cleaner and safer. Reported-by: Gilles BULOZ <gilles.buloz@kontron.com> Closes: https://lore.kernel.org/lkml/aLsw6G0GyqfpKs2S@mail.minyard.net/ Fixes: 8e76741c3d8b ("ipmi: Add a limit on the number of users that may use IPMI") Cc: <stable@vger.kernel.org> # 4.19 Signed-off-by: Corey Minyard <corey@minyard.net> Tested-by: Gilles BULOZ <gilles.buloz@kontron.com>
2025-09-08Revert "ipmi: fix msg stack when IPMI is disconnected"Corey Minyard-11/+5
This reverts commit c608966f3f9c2dca596967501d00753282b395fc. This patch has a subtle bug that can cause the IPMI driver to go into an infinite loop if the BMC misbehaves in a certain way. Apparently certain BMCs do misbehave this way because several reports have come in recently about this. Signed-off-by: Corey Minyard <corey@minyard.net> Tested-by: Eric Hagberg <ehagberg@janestreet.com> Cc: <stable@vger.kernel.org> # 6.2
2025-09-08ipmi:msghandler:Change seq_lock to a mutexCorey Minyard-37/+26
Dan Carpenter got a Smatch warning: drivers/char/ipmi/ipmi_msghandler.c:5265 ipmi_free_recv_msg() warn: sleeping in atomic context due to the recent rework of the IPMI driver's locking. I didn't realize vfree could block. But there is an easy solution to this, now that almost everything in the message handler runs in thread context. I wanted to spend the time earlier to see if seq_lock could be converted from a spinlock to a mutex, but I wanted the previous changes to go in and soak before I did that. So I went ahead and did the analysis and converting should work. And solve this problem. Reported-by: kernel test robot <lkp@intel.com> Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Closes: https://lore.kernel.org/r/202503240244.LR7pOwyr-lkp@intel.com/ Fixes: 3be997d5a64a ("ipmi:msghandler: Remove srcu from the ipmi user structure") Cc: <stable@vger.kernel.org> # 6.16 Signed-off-by: Corey Minyard <corey@minyard.net>
2025-08-07Merge tag 'for-linus-6.17-1' of https://github.com/cminyard/linux-ipmiLinus Torvalds-25/+46
Pull ipmi updates from Corey Minyard: "Some small fixes for the IPMI driver Nothing huge, some rate limiting on logs, a strncpy fix where the source and destination could be the same, and removal of some unused cruft" * tag 'for-linus-6.17-1' of https://github.com/cminyard/linux-ipmi: ipmi: Use dev_warn_ratelimited() for incorrect message warnings char: ipmi: remove redundant variable 'type' and check ipmi: Fix strcpy source and destination the same
2025-07-10ipmi: Use dev_warn_ratelimited() for incorrect message warningsBreno Leitao-4/+4
During BMC firmware upgrades on live systems, the ipmi_msghandler generates excessive "BMC returned incorrect response" warnings while the BMC is temporarily offline. This can flood system logs in large deployments. Replace dev_warn() with dev_warn_ratelimited() to throttle these warnings and prevent log spam during BMC maintenance operations. Signed-off-by: Breno Leitao <leitao@debian.org> Message-ID: <20250710-ipmi_ratelimit-v1-1-6d417015ebe9@debian.org> Signed-off-by: Corey Minyard <corey@minyard.net>
2025-07-08char: ipmi: remove redundant variable 'type' and checkColin Ian King-4/+0
The variable 'type' is assigned the value SI_INVALID which is zero and later checks of 'type' is non-zero (which is always false). The variable is not referenced anywhere else, so it is redundant and so is the check, so remove these. Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Message-ID: <20250708151805.1893858-1-colin.i.king@gmail.com> Signed-off-by: Corey Minyard <corey@minyard.net>
2025-06-13ipmi: Fix strcpy source and destination the sameCorey Minyard-17/+42
The source and destination of some strcpy operations was the same. Split out the part of the operations that needed to be done for those particular calls so the unnecessary copy wasn't done. Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202506140756.EFXXvIP4-lkp@intel.com/ Signed-off-by: Corey Minyard <corey@minyard.net>
2025-06-08treewide, timers: Rename from_timer() to timer_container_of()Ingo Molnar-5/+9
Move this API to the canonical timer_*() namespace. [ tglx: Redone against pre rc1 ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/aB2X0jCKQO56WdMt@gmail.com
2025-05-07ipmi:msghandler: Fix potential memory corruption in ipmi_create_user()Dan Carpenter-2/+3
The "intf" list iterator is an invalid pointer if the correct "intf->intf_num" is not found. Calling atomic_dec(&intf->nr_users) on and invalid pointer will lead to memory corruption. We don't really need to call atomic_dec() if we haven't called atomic_add_return() so update the if (intf->in_shutdown) path as well. Fixes: 8e76741c3d8b ("ipmi: Add a limit on the number of users that may use IPMI") Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Message-ID: <aBjMZ8RYrOt6NOgi@stanley.mountain> Signed-off-by: Corey Minyard <corey@minyard.net>
2025-05-07ipmi:watchdog: Use the new interface for panic messagesCorey Minyard-55/+17
It's available, remove all the duplicate code. Signed-off-by: Corey Minyard <cminyard@mvista.com>
2025-05-07ipmi:msghandler: Export and fix panic messaging capabilityCorey Minyard-19/+31
Don't have the other users that do things at panic time (the watchdog) do all this themselves, provide a function to do it. Also, with the new design where most stuff happens at thread context, a few things needed to be fixed to avoid doing locking in a panic context. Signed-off-by: Corey Minyard <cminyard@mvista.com>
2025-05-07ipmi:ssif: Fix a shutdown raceCorey Minyard-5/+1
It was possible for the SSIF thread to stop and quit before the kthread_stop() call because ssif->stopping was set before the stop. So only exit the SSIF thread is kthread_should_stop() returns true. There is no need to wake the thread, as the wait will be interrupted by kthread_stop(). Signed-off-by: Corey Minyard <cminyard@mvista.com>