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| author | Michael Ellerman <mpe@ellerman.id.au> | 2022-04-06 17:57:59 +0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2022-04-27 14:57:36 +0300 |
| commit | 0d897255e79e26f471d10bbf72db9eee6f9cb723 (patch) | |
| tree | 66cf81b9c266af07030ae02009ba30fd07289854 /arch/powerpc/platforms/85xx | |
| parent | 3527e1ab9a7990530dfb0137ddcfa64bed2915be (diff) | |
| download | linux-0d897255e79e26f471d10bbf72db9eee6f9cb723.tar.xz | |
powerpc/85xx: Fix virt_to_phys() off-by-one in smp_85xx_start_cpu()
In smp_85xx_start_cpu() we are passed an address but we're unsure if
it's a real or virtual address, so there's a check to determine that.
The check has an off-by-one in that it tests if the address is greater
than high_memory, but high_memory is the first address of high memory,
so the check should be greater-or-equal.
It seems this has never been a problem in practice, but it also triggers
the DEBUG_VIRTUAL checks in __pa() which we would like to avoid. We can
fix both issues by converting high_memory - 1 to a physical address and
testing against that.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220406145802.538416-3-mpe@ellerman.id.au
Diffstat (limited to 'arch/powerpc/platforms/85xx')
| -rw-r--r-- | arch/powerpc/platforms/85xx/smp.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c index a1c6a7827c8f..9c43cf32f4c9 100644 --- a/arch/powerpc/platforms/85xx/smp.c +++ b/arch/powerpc/platforms/85xx/smp.c @@ -208,7 +208,7 @@ static int smp_85xx_start_cpu(int cpu) * The bootpage and highmem can be accessed via ioremap(), but * we need to directly access the spinloop if its in lowmem. */ - ioremappable = *cpu_rel_addr > virt_to_phys(high_memory); + ioremappable = *cpu_rel_addr > virt_to_phys(high_memory - 1); /* Map the spin table */ if (ioremappable) |