| Message ID | 20190926125545.21745-1-ajd@linux.ibm.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | npu2-opencapi: Fix integer promotion bug in LPC allocation | expand |
On Thu, Sep 26, 2019 at 10:57 PM Andrew Donnellan <ajd@linux.ibm.com> wrote: > > If you try to allocate an amount of LPC memory that's not a power of 2, > we round the value up to the nearest power of 2. > > By the magic of C, "1 << n" gets treated as an int, even if you're > assigning it to a uint64_t. > > Change 1 to 1ULL to fix this. > > (C, it's great.) > > Reported-by: Alastair D'Silva <alistair@d-silva.org> > Cc: skiboot-stable@lists.ozlabs.org > Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> Merged as of e85e2e2b8b0a4dd96e10343df19df1a161cd6aac
On 9/26/19 6:25 PM, Andrew Donnellan wrote: > If you try to allocate an amount of LPC memory that's not a power of 2, > we round the value up to the nearest power of 2. > > By the magic of C, "1 << n" gets treated as an int, even if you're > assigning it to a uint64_t. > > Change 1 to 1ULL to fix this. > > (C, it's great.) > > Reported-by: Alastair D'Silva <alistair@d-silva.org> > Cc: skiboot-stable@lists.ozlabs.org skiboot v6.5.2 stable release contains this fix. -Vasant
diff --git a/hw/npu2-opencapi.c b/hw/npu2-opencapi.c index 9a391bb01461..a54ef63a86f8 100644 --- a/hw/npu2-opencapi.c +++ b/hw/npu2-opencapi.c @@ -2135,7 +2135,7 @@ static int64_t alloc_mem_bar(struct npu2_dev *dev, uint64_t size, uint64_t *bar) } if (!is_pow2(size)) { - size = 1 << (ilog2(size) + 1); + size = 1ull << (ilog2(size) + 1); } set_mem_bar(dev, phys_map_base, size);
If you try to allocate an amount of LPC memory that's not a power of 2, we round the value up to the nearest power of 2. By the magic of C, "1 << n" gets treated as an int, even if you're assigning it to a uint64_t. Change 1 to 1ULL to fix this. (C, it's great.) Reported-by: Alastair D'Silva <alistair@d-silva.org> Cc: skiboot-stable@lists.ozlabs.org Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> --- Alastair: please double check this fixes whatever issue you were seeing --- hw/npu2-opencapi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)