diff options
author | Ben Fradella <bfradell@netapp.com> | 2024-05-09 19:49:34 +0300 |
---|---|---|
committer | Hans de Goede <hdegoede@redhat.com> | 2024-05-14 12:43:39 +0300 |
commit | 2c6370e6607663fc5fa0fd9ed58e2e01014898c7 (patch) | |
tree | 2e948229e0ce5cf5c1ece8068cafd20c330a80f6 /drivers/platform | |
parent | 7c4cd2afee68aea873c0c1fb729ba309f945510c (diff) | |
download | linux-2c6370e6607663fc5fa0fd9ed58e2e01014898c7.tar.xz |
platform/x86: p2sb: Don't init until unassigned resources have been assigned
The P2SB could get an invalid BAR from the BIOS, and that won't be fixed
up until pcibios_assign_resources(), which is an fs_initcall().
- Move p2sb_fs_init() to an fs_initcall_sync(). This is still early
enough to avoid a race with any dependent drivers.
- Add a check for IORESOURCE_UNSET in p2sb_valid_resource() to catch
unset BARs going forward.
- Return error values from p2sb_fs_init() so that the 'initcall_debug'
cmdline arg provides useful data.
Signed-off-by: Ben Fradella <bfradell@netapp.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Klara Modin <klarasmodin@gmail.com>
Reviewed-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Link: https://lore.kernel.org/r/20240509164905.41016-1-bcfradella@proton.me
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Diffstat (limited to 'drivers/platform')
-rw-r--r-- | drivers/platform/x86/p2sb.c | 29 |
1 files changed, 15 insertions, 14 deletions
diff --git a/drivers/platform/x86/p2sb.c b/drivers/platform/x86/p2sb.c index 53fe96b99ab7..3bf5d2243491 100644 --- a/drivers/platform/x86/p2sb.c +++ b/drivers/platform/x86/p2sb.c @@ -55,12 +55,9 @@ static void p2sb_get_devfn(unsigned int *devfn) *devfn = fn; } -static bool p2sb_valid_resource(struct resource *res) +static bool p2sb_valid_resource(const struct resource *res) { - if (res->flags) - return true; - - return false; + return res->flags & ~IORESOURCE_UNSET; } /* Copy resource from the first BAR of the device in question */ @@ -213,16 +210,20 @@ EXPORT_SYMBOL_GPL(p2sb_bar); static int __init p2sb_fs_init(void) { - p2sb_cache_resources(); - return 0; + return p2sb_cache_resources(); } /* - * pci_rescan_remove_lock to avoid access to unhidden P2SB devices can - * not be locked in sysfs pci bus rescan path because of deadlock. To - * avoid the deadlock, access to P2SB devices with the lock at an early - * step in kernel initialization and cache required resources. This - * should happen after subsys_initcall which initializes PCI subsystem - * and before device_initcall which requires P2SB resources. + * pci_rescan_remove_lock() can not be locked in sysfs PCI bus rescan path + * because of deadlock. To avoid the deadlock, access P2SB devices with the lock + * at an early step in kernel initialization and cache required resources. + * + * We want to run as early as possible. If the P2SB was assigned a bad BAR, + * we'll need to wait on pcibios_assign_resources() to fix it. So, our list of + * initcall dependencies looks something like this: + * + * ... + * subsys_initcall (pci_subsys_init) + * fs_initcall (pcibios_assign_resources) */ -fs_initcall(p2sb_fs_init); +fs_initcall_sync(p2sb_fs_init); |