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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-10-02 12:17:24 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-10-02 12:17:24 -0700 |
| commit | 3f1fe48a36b0b6722dc3fd421d93512bac138e9a (patch) | |
| tree | b767d7f6e26bc64334d3f14f8422d187239dc45d /drivers/acpi/reboot.c | |
| download | linux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.tar.gz linux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.zip | |
Merge tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linuxgrafted
Pull io_uring fixes from Jens Axboe:
- Fix a task_work add use-after-free with SQPOLL.
The sqpoll thread could pop and complete the last request while
io_req_normal_work_add() was still looking at them after the mpscq
push.
Use the same approach as DEFER_TASKRUN to protect from that, holding
an RCU read lock across the add, and have exit wait for an RCU grace
period for SQPOLL rings as well.
- CQE32 ring fixes: correct the free entry check for 32b CQEs, zero the
big_cqe for aux CQEs, and only post the dummy skip CQE on CQE_MIXED
rings
- Mark the source filter table as COW when cloning bpf filters, so
registering another filter on the source doesn't modify the shared
table in place
- Initialize the task context before running the BPF loop
- Requeue zcrx multishot receives stopped by a local resource
- End a TX_TIMESTAMP multishot cmd when the CQ is full (lollipopkit)
* tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
io_uring: fix task_work add use-after-free with SQPOLL
io_uring/cmd_net: end TX_TIMESTAMP multishot when the CQ is full
io_uring/zcrx: requeue multishot receives stopped by a local resource
io_uring: initialize task context before running the BPF loop
io_uring: zero big_cqe for aux CQEs on CQE32 rings
io_uring: fix free entry check for 32b CQEs on CQE32 rings
io_uring: only post the dummy skip CQE on CQE_MIXED rings
io_uring/bpf_filter: mark source as COW when cloning filters
Diffstat (limited to 'drivers/acpi/reboot.c')
| -rw-r--r-- | drivers/acpi/reboot.c | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/drivers/acpi/reboot.c b/drivers/acpi/reboot.c new file mode 100644 index 000000000..b79b7c99c --- /dev/null +++ b/drivers/acpi/reboot.c @@ -0,0 +1,82 @@ +// SPDX-License-Identifier: GPL-2.0 + +#define pr_fmt(fmt) "ACPI: " fmt + +#include <linux/pci.h> +#include <linux/acpi.h> +#include <acpi/reboot.h> +#include <linux/delay.h> + +#ifdef CONFIG_PCI +static void acpi_pci_reboot(struct acpi_generic_address *rr, u8 reset_value) +{ + unsigned int devfn; + struct pci_bus *bus0; + + /* The reset register can only live on bus 0. */ + bus0 = pci_find_bus(0, 0); + if (!bus0) + return; + /* Form PCI device/function pair. */ + devfn = PCI_DEVFN((rr->address >> 32) & 0xffff, + (rr->address >> 16) & 0xffff); + pr_debug("Resetting with ACPI PCI RESET_REG.\n"); + /* Write the value that resets us. */ + pci_bus_write_config_byte(bus0, devfn, + (rr->address & 0xffff), reset_value); +} +#else +static inline void acpi_pci_reboot(struct acpi_generic_address *rr, + u8 reset_value) +{ + pr_warn_once("PCI configuration space access is not supported\n"); +} +#endif + +void acpi_reboot(void) +{ + struct acpi_generic_address *rr; + u8 reset_value; + + if (acpi_disabled) + return; + + rr = &acpi_gbl_FADT.reset_register; + + /* ACPI reset register was only introduced with v2 of the FADT */ + + if (acpi_gbl_FADT.header.revision < 2) + return; + + /* Is the reset register supported? The spec says we should be + * checking the bit width and bit offset, but Windows ignores + * these fields */ + if (!(acpi_gbl_FADT.flags & ACPI_FADT_RESET_REGISTER)) + return; + + reset_value = acpi_gbl_FADT.reset_value; + + /* The reset register can only exist in I/O, Memory or PCI config space + * on a device on bus 0. */ + switch (rr->space_id) { + case ACPI_ADR_SPACE_PCI_CONFIG: + acpi_pci_reboot(rr, reset_value); + break; + + case ACPI_ADR_SPACE_SYSTEM_MEMORY: + case ACPI_ADR_SPACE_SYSTEM_IO: + pr_debug("ACPI MEMORY or I/O RESET_REG.\n"); + acpi_reset(); + break; + } + + /* + * Some platforms do not shut down immediately after writing to the + * ACPI reset register, and this results in racing with the + * subsequent reboot mechanism. + * + * The 15ms delay has been found to be long enough for the system + * to reboot on the affected platforms. + */ + mdelay(15); +} |
