n Thu, Jan 13, 2022 at 04:28:39PM -0800, Lucas De Marchi wrote:
early_pci_scan_bus() does a depth-first traversal, possibly calling the quirk functions for each device based on vendor, device and class from early_qrk table. intel_graphics_quirks() however uses PCI_ANY_ID and does additional filtering in the quirk.
If there is an Intel integrated + discrete GPU the quirk may be called first for the discrete GPU based on the PCI topology. Then we will fail to reserve the system stolen memory for the integrated GPU, because we will already have marked the quirk as "applied".
Who is "we"?
Please use passive voice in your commit message: no "we" or "I", etc, and describe your changes in imperative mood.
Bottom line is: personal pronouns are ambiguous in text, especially with so many parties/companies/etc developing the kernel so let's avoid them please.
This was reproduced in a setup with Alderlake-P (integrated) + DG2 (discrete), with the following PCI topology:
- 00:01.0 Bridge `- 03:00.0 DG2
- 00:02.0 Integrated GPU
So, stop using the QFLAG_APPLY_ONCE flag, replacing it with a static local variable. We can set this variable in the right place, inside intel_graphics_quirks(), only when the quirk was actually applied, i.e. when we find the integrated GPU based on the intel_early_ids table.
Cc: stable@vger.kernel.org Signed-off-by: Lucas De Marchi lucas.demarchi@intel.com
v5: apply fix before the refactor
arch/x86/kernel/early-quirks.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kernel/early-quirks.c b/arch/x86/kernel/early-quirks.c index 1ca3a56fdc2d..de9a76eb544e 100644 --- a/arch/x86/kernel/early-quirks.c +++ b/arch/x86/kernel/early-quirks.c @@ -589,10 +589,14 @@ intel_graphics_stolen(int num, int slot, int func, static void __init intel_graphics_quirks(int num, int slot, int func) {
- static bool quirk_applied __initdata; const struct intel_early_ops *early_ops; u16 device; int i;
- if (quirk_applied)
return;- device = read_pci_config_16(num, slot, func, PCI_DEVICE_ID);
for (i = 0; i < ARRAY_SIZE(intel_early_ids); i++) { @@ -605,6 +609,8 @@ static void __init intel_graphics_quirks(int num, int slot, int func) intel_graphics_stolen(num, slot, func, early_ops);
quirk_applied = true;- return; }
So I wonder: why can't you simply pass in a static struct chipset * pointer into the early_qrk[i].f function and in there you can set QFLAG_APPLIED or so, so that you can mark that the quirk is applied by using the nice, per-quirk flags someone has already added instead of this ugly static variable?
Patch 3 especially makes me go, huh?