PCI: Use ioremap(), not phys_to_virt() for platform ROM
[ Upstream commit 72e0ef0e5f067fd991f702f0b2635d911d0cf208 ]
On some EFI systems, the video BIOS is provided by the EFI firmware. The
boot stub code stores the physical address of the ROM image in pdev->rom.
Currently we attempt to access this pointer using phys_to_virt(), which
doesn't work with CONFIG_HIGHMEM.
On these systems, attempting to load the radeon module on a x86_32 kernel
can result in the following:
BUG: unable to handle page fault for address: 3e8ed03c
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
*pde = 00000000
Oops: 0000 [#1] PREEMPT SMP
CPU: 0 PID: 317 Comm: systemd-udevd Not tainted 5.6.0-rc3-next-20200228 #2
Hardware name: Apple Computer, Inc. MacPro1,1/Mac-F4208DC8, BIOS MP11.88Z.005C.B08.0707021221 07/02/07
EIP: radeon_get_bios+0x5ed/0xe50 [radeon]
Code: 00 00 84 c0 0f 85 12 fd ff ff c7 87 64 01 00 00 00 00 00 00 8b 47 08 8b 55 b0 e8 1e 83 e1 d6 85 c0 74 1a 8b 55 c0 85 d2 74 13 <80> 38 55 75 0e 80 78 01 aa 0f 84 a4 03 00 00 8d 74 26 00 68 dc 06
EAX: 3e8ed03c EBX: 00000000 ECX: 3e8ed03c EDX: 00010000
ESI: 00040000 EDI: eec04000 EBP: eef3fc60 ESP: eef3fbe0
DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00010206
CR0: 80050033 CR2: 3e8ed03c CR3: 2ec77000 CR4: 000006d0
Call Trace:
r520_init+0x26/0x240 [radeon]
radeon_device_init+0x533/0xa50 [radeon]
radeon_driver_load_kms+0x80/0x220 [radeon]
drm_dev_register+0xa7/0x180 [drm]
radeon_pci_probe+0x10f/0x1a0 [radeon]
pci_device_probe+0xd4/0x140
Fix the issue by updating all drivers which can access a platform provided
ROM. Instead of calling the helper function pci_platform_rom() which uses
phys_to_virt(), call ioremap() directly on the pdev->rom.
radeon_read_platform_bios() previously directly accessed an __iomem
pointer. Avoid this by calling memcpy_fromio() instead of kmemdup().
pci_platform_rom() now has no remaining callers, so remove it.
Link: https://lore.kernel.org/r/20200319021623.5426-1-mikel@mikelr.com
Signed-off-by: Mikel Rychliski <mikel@mikelr.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 files changed