[GIT RFC PULL] Fix double dereference in TP_printk() in usb mtu3

From: Paul E. McKenney

Date: Wed Oct 07 2026 - 16:23:49 EST


Hello, Linus,

Please pull this urgent fix for a tracing splat in usb mtu3, which is a
pre-existing bug that can corrupt tracing output, but which was exposed
this cycle by additional checking that was added to the tracing subsystem.

git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git tags/usb-mtu3.2026.10.06a
# HEAD: cfb3293c4573289f11f913611f530ea6b1926d67: usb: mtu3: Fix double dereference in TP_printk (2026-09-29 17:26:50 -0700)

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usb: mtu3: Fix a double-dereference splat in TP_printk

This splat is reporting a double-dereference that can result in garbage
traces being dumped due to the possibility of the TP_printk() being
executed without the benefit of main memory being present. The fix is to
move the extra dereference from TP_printk() time to TP_fast_assign() time.

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Vladimir Murzin (1):
usb: mtu3: Fix double dereference in TP_printk

drivers/usb/mtu3/mtu3_trace.h | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)