Unverified Commit 1d7461d0 authored by David E. Box's avatar David E. Box Committed by Ilpo Järvinen
Browse files

platform/x86: intel/pmc: Fix ioremap() of bad address 



In pmc_core_ssram_get_pmc(), the physical addresses for hidden SSRAM
devices are retrieved from the MMIO region of the primary SSRAM device.
If additional devices are not present, the address returned is zero.
Currently, the code does not check for this condition, resulting in
ioremap() incorrectly attempting to map address 0.

Add a check for a zero address and return 0 if no additional devices
are found, as it is not an error for the device to be absent.

Fixes: a01486dc ("platform/x86/intel/pmc: Cleanup SSRAM discovery")
Signed-off-by: default avatarDavid E. Box <david.e.box@linux.intel.com>
Link: https://lore.kernel.org/r/20250106174653.1497128-1-david.e.box@linux.intel.com


Reviewed-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
parent cc1ff7bc

drivers/platform/x86/intel/pmc/core_ssram.c

+4 −0
Original line number Diff line number Diff line
@@ -269,8 +269,12 @@ pmc_core_ssram_get_pmc(struct pmc_dev *pmcdev, int pmc_idx, u32 offset) 
		/*

		 * The secondary PMC BARS (which are behind hidden PCI devices)

		 * are read from fixed offsets in MMIO of the primary PMC BAR.

		 * If a device is not present, the value will be 0.

		 */

		ssram_base = get_base(tmp_ssram, offset);

		if (!ssram_base)

			return 0;



		ssram = ioremap(ssram_base, SSRAM_HDR_SIZE);

		if (!ssram)

			return -ENOMEM;