[PATCH stable 5.10 v2 0/4] ARM FDT relocation backports

From: Florian Fainelli
Date: Mon May 10 2021 - 09:26:10 EST


Hi Greg, Sasha,

These patches were not marked with a Fixes: tag but they do fix booting
ARM 32-bit platforms that have specific FDT placement and would cause
boot failures like these:

[ 0.000000] 8<--- cut here ---
[ 0.000000] Unable to handle kernel paging request at virtual address
ffa14000
[ 0.000000] pgd = (ptrval)
[ 0.000000] [ffa14000] *pgd=80000040007003, *pmd=00000000
[ 0.000000] Internal error: Oops: 206 [#1] SMP ARM
[ 0.000000] Modules linked in:
[ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 5.4.85-1.0 #1
[ 0.000000] Hardware name: Broadcom STB (Flattened Device Tree)
[ 0.000000] PC is at fdt_check_header+0xc/0x21c
[ 0.000000] LR is at __unflatten_device_tree+0x7c/0x2f8
[ 0.000000] pc : [<c0d30e44>] lr : [<c0a6c0fc>] psr: 600000d3
[ 0.000000] sp : c1401eac ip : c1401ec8 fp : c1401ec4
[ 0.000000] r10: 00000000 r9 : c150523c r8 : 00000000
[ 0.000000] r7 : c124eab4 r6 : ffa14000 r5 : 00000000 r4 :
c14ba920
[ 0.000000] r3 : 00000000 r2 : c150523c r1 : 00000000 r0 :
ffa14000
[ 0.000000] Flags: nZCv IRQs off FIQs off Mode SVC_32 ISA ARM
Segment user
[ 0.000000] Control: 30c5383d Table: 40003000 DAC: fffffffd
[ 0.000000] Process swapper (pid: 0, stack limit = 0x(ptrval))
[ 0.000000] Stack: (0xc1401eac to 0xc1402000)
[ 0.000000] 1ea0: c14ba920 00000000
ffa14000 c1401ef4 c1401ec8
[ 0.000000] 1ec0: c0a6c0fc c0d30e44 c124eab4 c124eab4 00000000
c14ebfc0 c140e5b8 00000000
[ 0.000000] 1ee0: 00000001 c126f5a0 c1401f14 c1401ef8 c1250064
c0a6c08c 00000000 c1401f08
[ 0.000000] 1f00: c022ddac c140ce80 c1401f9c c1401f18 c120506c
c125002c 00000000 00000000
[ 0.000000] 1f20: 00000000 00000000 ffffffff c1401f94 c1401f6c
c1406308 3fffffff 00000001
[ 0.000000] 1f40: 00000000 00000001 c1432b58 c14ca180 c1213ca4
c1406308 c1406300 30c0387d
[ 0.000000] 1f60: c1401f8c c1401f70 c028e0ec 00000000 c1401f94
c1406308 c1406300 30c0387d
[ 0.000000] 1f80: 00000000 7fa14000 420f1000 30c5387d c1401ff4
c1401fa0 c1200c98 c120467c
[ 0.000000] 1fa0: 00000000 00000000 00000000 00000000 00000000
00000000 00000000 c127fa44
[ 0.000000] 1fc0: 00000000 00000000 00000000 c1200330 00000000
30c0387d ffffffff 7fa14000
[ 0.000000] 1fe0: 420f1000 30c5387d 00000000 c1401ff8 00000000
c1200c28 00000000 00000000
[ 0.000000] Backtrace:
[ 0.000000] [<c0d30e38>] (fdt_check_header) from [<c0a6c0fc>]
(__unflatten_device_tree+0x7c/0x2f8)
[ 0.000000] r6:ffa14000 r5:00000000 r4:c14ba920
[ 0.000000] [<c0a6c080>] (__unflatten_device_tree) from [<c1250064>]
(unflatten_device_tree+0x44/0x54)
[ 0.000000] r10:c126f5a0 r9:00000001 r8:00000000 r7:c140e5b8
r6:c14ebfc0 r5:00000000
[ 0.000000] r4:c124eab4 r3:c124eab4
[ 0.000000] [<c1250020>] (unflatten_device_tree) from [<c120506c>]
(setup_arch+0x9fc/0xc84)
[ 0.000000] r4:c140ce80
[ 0.000000] [<c1204670>] (setup_arch) from [<c1200c98>]
(start_kernel+0x7c/0x540)
[ 0.000000] r10:30c5387d r9:420f1000 r8:7fa14000 r7:00000000
r6:30c0387d r5:c1406300
[ 0.000000] r4:c1406308
[ 0.000000] [<c1200c1c>] (start_kernel) from [<00000000>] (0x0)
[ 0.000000] r10:30c5387d r9:420f1000 r8:7fa14000 r7:ffffffff
r6:30c0387d r5:00000000
[ 0.000000] r4:c1200330
[ 0.000000] Code: e89da800 e1a0c00d e92dd870 e24cb004 (e5d03000)
[ 0.000000] random: get_random_bytes called from
print_oops_end_marker+0x50/0x58 with crng_init=0
[ 0.000000] ---[ end trace f34b4929828506c1 ]---
[ 0.000000] Kernel panic - not syncing: Attempted to kill the idle
task!
[ 0.000000] ---[ end Kernel panic - not syncing: Attempted to kill
the idle task! ]---

Changes in v2:

- include "ARM: 9027/1: head.S: explicitly map DT even if it lives in
the first physical section" as suggested by Ard.

Ard Biesheuvel (4):
ARM: 9011/1: centralize phys-to-virt conversion of DT/ATAGS address
ARM: 9012/1: move device tree mapping out of linear region
ARM: 9020/1: mm: use correct section size macro to describe the FDT
virtual address
ARM: 9027/1: head.S: explicitly map DT even if it lives in the first
physical section

Documentation/arm/memory.rst | 7 ++++++-
arch/arm/include/asm/fixmap.h | 2 +-
arch/arm/include/asm/memory.h | 5 +++++
arch/arm/include/asm/prom.h | 4 ++--
arch/arm/kernel/atags.h | 4 ++--
arch/arm/kernel/atags_parse.c | 6 +++---
arch/arm/kernel/devtree.c | 6 +++---
arch/arm/kernel/head.S | 9 ++++-----
arch/arm/kernel/setup.c | 19 ++++++++++++++-----
arch/arm/mm/init.c | 1 -
arch/arm/mm/mmu.c | 20 ++++++++++++++------
arch/arm/mm/pv-fixup-asm.S | 4 ++--
12 files changed, 56 insertions(+), 31 deletions(-)

--
2.25.1