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Janek Kotas
931c4e9a72
The path "spi: cadence: Add usleep_range() for cdns_spi_fill_tx_fifo()" added a usleep_range() function call, which cannot be used in atomic context. However the cdns_spi_fill_tx_fifo() function can be called during an interrupt which may result in a kernel panic: BUG: scheduling while atomic: grep/561/0x00010002 Modules linked in: Preemption disabled at: [<ffffff800858ea28>] wait_for_common+0x48/0x178 CPU: 0 PID: 561 Comm: grep Not tainted 4.17.0 #1 Hardware name: Cadence CSP (DT) Call trace: dump_backtrace+0x0/0x198 show_stack+0x14/0x20 dump_stack+0x8c/0xac __schedule_bug+0x6c/0xb8 __schedule+0x570/0x5d8 schedule+0x34/0x98 schedule_hrtimeout_range_clock+0x98/0x110 schedule_hrtimeout_range+0x10/0x18 usleep_range+0x64/0x98 cdns_spi_fill_tx_fifo+0x70/0xb0 cdns_spi_irq+0xd0/0xe0 __handle_irq_event_percpu+0x9c/0x128 handle_irq_event_percpu+0x34/0x88 handle_irq_event+0x48/0x78 handle_fasteoi_irq+0xbc/0x1b0 generic_handle_irq+0x24/0x38 __handle_domain_irq+0x84/0xf8 gic_handle_irq+0xc4/0x180 This patch replaces the function call with udelay() which can be used in an atomic context, like an interrupt. Signed-off-by: Jan Kotas <jank@cadence.com> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org
Linux kernel
============
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