[PATCH v2] powerpc/iommu: limit number of TCEs to 512 for H_STUFF_TCE hcall
From: Gaurav Batra <hidden>
Date: 2023-05-25 14:35:13
Also in:
stable
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
As of now, in tce_freemulti_pSeriesLP(), there is no limit on how many TCEs are passed to H_STUFF_TCE hcall. This was not an issue until now. Newer firmware releases have started enforcing this requirement. The interface has been in it's current form since the beginning. Cc: stable@vger.kernel.org Signed-off-by: Gaurav Batra <redacted> Reviewed-by: Brian King <redacted> --- arch/powerpc/platforms/pseries/iommu.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c
index c74b71d4733d..f159a195101d 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c@@ -306,13 +306,22 @@ static void tce_free_pSeriesLP(unsigned long liobn, long tcenum, long tceshift, static void tce_freemulti_pSeriesLP(struct iommu_table *tbl, long tcenum, long npages) { u64 rc; + long rpages = npages; + unsigned long limit; if (!firmware_has_feature(FW_FEATURE_STUFF_TCE)) return tce_free_pSeriesLP(tbl->it_index, tcenum, tbl->it_page_shift, npages); - rc = plpar_tce_stuff((u64)tbl->it_index, - (u64)tcenum << tbl->it_page_shift, 0, npages); + do { + limit = min_t(unsigned long, rpages, 512); + + rc = plpar_tce_stuff((u64)tbl->it_index, + (u64)tcenum << tbl->it_page_shift, 0, limit); + + rpages -= limit; + tcenum += limit; + } while (rpages > 0 && !rc); if (rc && printk_ratelimit()) { printk("tce_freemulti_pSeriesLP: plpar_tce_stuff failed\n");
--
2.39.2 (Apple Git-143)