Re: [PATCH v5] arm pl011 serial: support multi-irq request

Qian Cai
2021-07-23T16:47:52Z

On 6/30/2021 9:38 PM, Bing Fan wrote:
> From: Bing Fan <tombinfan@tencent.com>
>
> In order to make pl011 work better, multiple interrupts are
> required, such as TXIM, RXIM, RTIM, error interrupt(FE/PE/BE/OE);
> at the same time, pl011 to GIC does not merge the interrupt
> lines(each serial-interrupt corresponding to different GIC hardware
> interrupt), so need to enable and request multiple gic interrupt
> numbers in the driver.
>
> Signed-off-by: Bing Fan <tombinfan@tencent.com>
> ---
> drivers/tty/serial/amba-pl011.c | 34 ++++++++++++++++++++++++++++++---
> 1 file changed, 31 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
> index 78682c12156a..7bfe8efcc787 100644
> --- a/drivers/tty/serial/amba-pl011.c
> +++ b/drivers/tty/serial/amba-pl011.c
> @@ -1701,11 +1701,39 @@ static void pl011_write_lcr_h(struct uart_amba_port *uap, unsigned int lcr_h)
> }
> }
>
> +static void pl011_release_irq(struct uart_amba_port *uap, unsigned int max_cnt)
> +{
> + struct amba_device *amba_dev = container_of(uap->port.dev, struct amba_device, dev);
> + int i;
> +
> + for (i = 0; i < max_cnt; i++)
> + if (amba_dev->irq[i])
> + free_irq(amba_dev->irq[i], uap);
> +}
> +
> static int pl011_allocate_irq(struct uart_amba_port *uap)
> {
> + int ret = 0;
> + int i;
> + unsigned int virq;
> + struct amba_device *amba_dev = container_of(uap->port.dev, struct amba_device, dev);
> +
> pl011_write(uap->im, uap, REG_IMSC);
>
> - return request_irq(uap->port.irq, pl011_int, IRQF_SHARED, "uart-pl011", uap);
> + for (i = 0; i < AMBA_NR_IRQS; i++) {
> + virq = amba_dev->irq[i];

This could trigger a slab-out-of-bounds during booting.

[ 18.716444] BUG: KASAN: slab-out-of-bounds in pl011_allocate_irq+0x1f8/0x2f8
[ 18.724191] Read of size 4 at addr ffff00001a3a0508 by task swapper/0/1

[ 18.733680] CPU: 5 PID: 1 Comm: swapper/0 Not tainted 5.14.0-rc2-next-20210723 #69
[ 18.741941] Hardware name: MiTAC RAPTOR EV-883832-X3-0001/RAPTOR, BIOS 1.6 06/28/2020
[ 18.750461] Call trace:
[ 18.753597] dump_backtrace+0x0/0x3b8
[ 18.757956] show_stack+0x20/0x30
[ 18.761964] dump_stack_lvl+0x8c/0xb8
[ 18.766319] print_address_description.constprop.0+0x74/0x3c8
[ 18.772759] kasan_report+0x1f0/0x208
[ 18.777113] __asan_report_load4_noabort+0x34/0x60
[ 18.782596] pl011_allocate_irq+0x1f8/0x2f8
[ 18.787471] sbsa_uart_startup+0x44/0x98
[ 18.792086] uart_startup.part.0+0x28c/0x618
[ 18.797048] uart_port_activate+0xf0/0x178
[ 18.801836] tty_port_open+0x118/0x1c8
[ 18.806278] uart_open+0x44/0x70
[ 18.810199] tty_open+0x248/0x960
[ 18.814207] chrdev_open+0x19c/0x440
[ 18.818476] do_dentry_open+0x3ac/0xdb0
[ 18.823005] vfs_open+0x98/0xd0
[ 18.826838] do_open.isra.0+0x4a8/0x8c0
[ 18.831366] path_openat+0x3ac/0xe28
[ 18.835633] do_filp_open+0x150/0x220
[ 18.839987] file_open_name+0x120/0x200
[ 18.844515] filp_open+0x40/0x80
[ 18.848436] console_on_rootfs+0x30/0x7c
[ 18.853052] kernel_init_freeable+0x74c/0x7d0
[ 18.858100] kernel_init+0x2c/0x140
[ 18.862282] ret_from_fork+0x10/0x18

[ 18.868732] Allocated by task 1:
[ 18.872651] kasan_save_stack+0x28/0x58
[ 18.877181] __kasan_kmalloc+0x8c/0xb0
[ 18.881622] __kmalloc+0x260/0x3d0
[ 18.885716] platform_device_alloc+0x34/0x1b8
[ 18.890766] platform_device_register_full+0x68/0x418
[ 18.896509] acpi_create_platform_device.part.0+0x170/0x538
[ 18.902776] acpi_create_platform_device+0x8c/0xa8
[ 18.908259] acpi_default_enumeration+0x54/0xd0
[ 18.913482] acpi_bus_attach+0x664/0x7d0
[ 18.918096] acpi_bus_attach+0x178/0x7d0
[ 18.922709] acpi_bus_attach+0x178/0x7d0
[ 18.927324] acpi_bus_attach+0x178/0x7d0
[ 18.931937] acpi_bus_scan+0xa8/0x170
[ 18.936291] acpi_scan_init+0x220/0x554
[ 18.940819] acpi_init+0x1fc/0x27c
[ 18.944912] do_one_initcall+0x170/0xb98
[ 18.949527] kernel_init_freeable+0x718/0x7d0
[ 18.954575] kernel_init+0x2c/0x140
[ 18.958759] ret_from_fork+0x10/0x18

[ 18.965214] The buggy address belongs to the object at ffff00001a3a0000
which belongs to the cache kmalloc-2k of size 2048
[ 18.979117] The buggy address is located 1288 bytes inside of
2048-byte region [ffff00001a3a0000, ffff00001a3a0800)
[ 18.992412] The buggy address belongs to the page:
[ 18.997894] page:ffffffc000068e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x9a38
[ 19.007805] head:ffffffc000068e00 order:2 compound_mapcount:0 compound_pincount:0
[ 19.015977] flags: 0x7ffff800010200(slab|head|node=0|zone=0|lastcpupid=0xfffff)
[ 19.023982] raw: 007ffff800010200 ffffffc000067508 ffffffc000069f08 ffff000012911280
[ 19.032416] raw: 0000000000000000 00000000002a002a 00000001ffffffff 0000000000000000
[ 19.040848] page dumped because: kasan: bad access detected

[ 19.049291] Memory state around the buggy address:
[ 19.054772] ffff00001a3a0400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 19.062684] ffff00001a3a0480: 00 00 00 00 00 00 00 00 00 00 00 04 fc fc fc fc
[ 19.070595] >ffff00001a3a0500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 19.078506] ^
[ 19.082686] ffff00001a3a0580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 19.090597] ffff00001a3a0600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc

> + if (virq == 0)
> + break;
> +
> + ret = request_irq(virq, pl011_int, IRQF_SHARED, dev_name(&amba_dev->dev), uap);
> + if (ret) {
> + dev_err(uap->port.dev, "request %u interrupt failed\n", virq);
> + pl011_release_irq(uap, i - 1);
> + break;
> + }
> + }
> +
> + return ret;
> }
>
> /*
> @@ -1864,7 +1892,7 @@ static void pl011_shutdown(struct uart_port *port)
>
> pl011_dma_shutdown(uap);
>
> - free_irq(uap->port.irq, uap);
> + pl011_release_irq(uap, AMBA_NR_IRQS);
>
> pl011_disable_uart(uap);
>
> @@ -1894,7 +1922,7 @@ static void sbsa_uart_shutdown(struct uart_port *port)
>
> pl011_disable_interrupts(uap);
>
> - free_irq(uap->port.irq, uap);
> + pl011_release_irq(uap, AMBA_NR_IRQS);
>
> if (uap->port.ops->flush_buffer)
> uap->port.ops->flush_buffer(port);
>