diff options
| author | Rafael J. Wysocki <rjw@sisk.pl> | 2011-02-08 23:48:16 +0100 |
|---|---|---|
| committer | Rafael J. Wysocki <rjw@sisk.pl> | 2011-02-24 19:59:00 +0100 |
| commit | 23fe36306ea489eef7dd88506bdcefdc8da39c91 (patch) | |
| tree | e788dffdc10ae283f737604f7cb476c13bcc1bce /drivers/acpi | |
| parent | mm: prevent concurrent unmap_mapping_range() on the same inode (diff) | |
| download | linux-23fe36306ea489eef7dd88506bdcefdc8da39c91.tar.xz linux-23fe36306ea489eef7dd88506bdcefdc8da39c91.zip | |
ACPI: Avoid calling request_irq() many times for the same interrupt
In principle acpi_os_install_interrupt_handler() may be called
multiple times for different interrupts, either from
acpi_ev_get_gpe_xrupt_block(), or from acpi_ev_install_sci_handler().
However, it always attempts to request the same interrupt,
acpi_gbl_FADT.sci_interrupt and it doesn't check whether or not this
interrupt has already been requested.
Modify this function so that it refuses to request interrupts other
than acpi_gbl_FADT.sci_interrupt and change
acpi_os_remove_interrupt_handler() so that it refuses to free such
interrupts. Use the observation that the only supported ACPI
interrupt must be equal to acpi_gbl_FADT.sci_interrupt and drop an
unnecessary variable acpi_irq_irq.
This change has been tested on Toshiba Portege R500 and HP nx6325
without introducing any visible problems.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/osl.c | 27 |
1 files changed, 15 insertions, 12 deletions
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index c90c76aa7f8b..187dff96356b 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -76,7 +76,6 @@ EXPORT_SYMBOL(acpi_in_debugger); extern char line_buf[80]; #endif /*ENABLE_DEBUGGER */ -static unsigned int acpi_irq_irq; static acpi_osd_handler acpi_irq_handler; static void *acpi_irq_context; static struct workqueue_struct *kacpid_wq; @@ -516,11 +515,15 @@ acpi_os_install_interrupt_handler(u32 gsi, acpi_osd_handler handler, acpi_irq_stats_init(); /* - * Ignore the GSI from the core, and use the value in our copy of the - * FADT. It may not be the same if an interrupt source override exists - * for the SCI. + * ACPI interrupts different from the SCI in our copy of the FADT are + * not supported. */ - gsi = acpi_gbl_FADT.sci_interrupt; + if (gsi != acpi_gbl_FADT.sci_interrupt) + return AE_BAD_PARAMETER; + + if (acpi_irq_handler) + return AE_ALREADY_ACQUIRED; + if (acpi_gsi_to_irq(gsi, &irq) < 0) { printk(KERN_ERR PREFIX "SCI (ACPI GSI %d) not registered\n", gsi); @@ -531,20 +534,20 @@ acpi_os_install_interrupt_handler(u32 gsi, acpi_osd_handler handler, acpi_irq_context = context; if (request_irq(irq, acpi_irq, IRQF_SHARED, "acpi", acpi_irq)) { printk(KERN_ERR PREFIX "SCI (IRQ%d) allocation failed\n", irq); + acpi_irq_handler = NULL; return AE_NOT_ACQUIRED; } - acpi_irq_irq = irq; return AE_OK; } acpi_status acpi_os_remove_interrupt_handler(u32 irq, acpi_osd_handler handler) { - if (irq) { - free_irq(irq, acpi_irq); - acpi_irq_handler = NULL; - acpi_irq_irq = 0; - } + if (irq != acpi_gbl_FADT.sci_interrupt) + return AE_BAD_PARAMETER; + + free_irq(irq, acpi_irq); + acpi_irq_handler = NULL; return AE_OK; } @@ -1603,7 +1606,7 @@ acpi_status __init acpi_os_initialize1(void) acpi_status acpi_os_terminate(void) { if (acpi_irq_handler) { - acpi_os_remove_interrupt_handler(acpi_irq_irq, + acpi_os_remove_interrupt_handler(acpi_gbl_FADT.sci_interrupt, acpi_irq_handler); } |