kernel/linux.git/drivers/char, branch v6.6.143

ipmi:ssif: NULL thread on error

2026-06-19T11:39:38+00:00

commit a8aebe93a4938c0ca1941eeaae821738f869be3d upstream. Cleanup code was checking the thread for NULL, but it was possibly a PTR_ERR() in one spot. Spotted with static analysis. Link: https://sourceforge.net/p/openipmi/mailman/message/59324676/ Fixes: 75c486cb1bca ("ipmi:ssif: Clean up kthread on errors") Cc: # 91eb7ec72612: ipmi:ssif: Remove unnecessary indention Cc: stable@vger.kernel.org Signed-off-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman

ipmi:ssif: Remove unnecessary indention

2026-06-19T11:39:37+00:00

commit 91eb7ec7261254b6875909df767185838598e21e upstream. 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 Signed-off-by: Greg Kroah-Hartman

ipmi: Fix rcu_read_unlock to srcu_read_unlock in handle_read_event_rsp

2026-06-19T11:39:28+00:00

Fix a bug where rcu_read_unlock() was used instead of srcu_read_unlock() in handle_read_event_rsp() when ipmi_alloc_recv_msg() fails. This mismatch leads to an SRCU read-side critical section imbalance: the entry uses srcu_read_lock(&intf->users_srcu) but the error path incorrectly calls rcu_read_unlock(), which is a no-op for SRCU and leaves the SRCU lock held. The offending code was restructured in mainline by commit 3be997d5a64a ("ipmi:msghandler: Remove srcu from the ipmi user structure"), which replaced the SRCU locking with a mutex in this function, effectively eliminating the mismatch. However, that commit is part of a larger SRCU removal series that is not suitable for stable backport. This minimal fix addresses the SRCU imbalance for 6.12 and earlier stable branches that still carry the original locking scheme. Fixes: e86ee2d44b44 ("ipmi: Rework locking and shutdown for hot remove") Cc: stable@vger.kernel.org Signed-off-by: Rui Qi Signed-off-by: Sasha Levin

ipmi: ssif_bmc: change log level to dbg in irq callback

2026-05-23T11:03:20+00:00

[ Upstream commit c9c99b7b7051eb7121b3224bfce181fb023b0269 ] 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 Message-ID: <20260403090603.3988423-4-zhangjian.3032@bytedance.com> Signed-off-by: Corey Minyard Signed-off-by: Sasha Levin

ipmi: ssif_bmc: fix message desynchronization after truncated response

2026-05-23T11:03:20+00:00

[ Upstream commit 1d38e849adb6851ee280aa1a1d687b2181549a66 ] 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 Message-ID: <20260403090603.3988423-3-zhangjian.3032@bytedance.com> Signed-off-by: Corey Minyard Signed-off-by: Sasha Levin

ipmi: ssif_bmc: fix missing check for copy_to_user() partial failure

2026-05-23T11:03:20+00:00

[ Upstream commit ea641be7a4faee4351f9c5ed6b188e1bbf5586a6 ] 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 Message-ID: <20260403090603.3988423-2-zhangjian.3032@bytedance.com> Signed-off-by: Corey Minyard Signed-off-by: Sasha Levin

ipmi:ssif: Clean up kthread on errors

2026-05-17T15:13:48+00:00

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 (cherry picked from commit 75c486cb1bcaa1a3ec3a6438498176a3a4998ae4) Signed-off-by: Greg Kroah-Hartman

ipmi:ssif: Fix a shutdown race

2026-05-17T15:13:48+00:00

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 (cherry picked from commit 6bd0eb6d759b9a22c5509ea04e19c2e8407ba418) Signed-off-by: Greg Kroah-Hartman

ipmi:si: Return state to normal if message allocation fails

2026-05-17T15:13:34+00:00

commit 09dd798270ff582d7309f285d4aaf5dbebae01cb upstream. There were places where nothing would get started if a message allocation failed, so the driver needs to return to normal state. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: Signed-off-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman

ipmi: Check event message buffer response for bad data

2026-05-17T15:13:34+00:00

commit 36920f30e78e69df01f9691c470b6f3ba8aebf98 upstream. The event message buffer response data size got checked later when processing, but check it right after the response comes back. It appears some BMCs may return an empty message instead of an error when fetching events. There are apparently some new BMCs that make this error, so we need to compensate. Reported-by: Matt Fleming Closes: https://lore.kernel.org/lkml/20260415115930.3428942-1-matt@readmodwrite.com/ Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: Signed-off-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman