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https://github.com/AuxXxilium/linux_dsm_epyc7002.git
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ffc661c99f
If ffz() ever returns a value >= 31 then the following shift is undefined behaviour because the literal 1 which gets shifted is treated as signed integer. In practice, the bug is probably harmless, since the first undefined shift count is 31 which results - ignoring UB - in (int)(0x80000000). This gets sign extended so bit 32-63 will be set as well and all subsequent __setup_irq() calls would just end up hitting the -EBUSY branch. However, a sufficiently aggressive optimizer may use the UB of 1<<31 to decide that doesn't happen, and hence elide the sign-extension code, so that subsequent calls can indeed get ffz > 31. In any case, the right thing to do is to make the literal 1UL. [ tglx: For this to happen a single interrupt would have to be shared by 32 devices. Hardware like that does not exist and would have way more problems than that. ] Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20171030213548.16831-1-linux@rasmusvillemoes.dk |
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| .. | ||
| affinity.c | ||
| autoprobe.c | ||
| chip.c | ||
| cpuhotplug.c | ||
| debug.h | ||
| debugfs.c | ||
| devres.c | ||
| dummychip.c | ||
| generic-chip.c | ||
| handle.c | ||
| internals.h | ||
| ipi.c | ||
| irq_sim.c | ||
| irqdesc.c | ||
| irqdomain.c | ||
| Kconfig | ||
| Makefile | ||
| manage.c | ||
| matrix.c | ||
| migration.c | ||
| msi.c | ||
| pm.c | ||
| proc.c | ||
| resend.c | ||
| settings.h | ||
| spurious.c | ||
| timings.c | ||