From: Yanfei Xu Date: Wed, 28 Aug 2024 08:42:28 +0000 (+0800) Subject: cxl/pci: Fix to record only non-zero ranges X-Git-Tag: v6.12-rc1~25^2~11 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=55e268694e8b07026c88191f9b6949b6887d9ce3;p=thirdparty%2Flinux.git cxl/pci: Fix to record only non-zero ranges The function cxl_dvsec_rr_decode() retrieves and records DVSEC ranges into info->dvsec_range[], regardless of whether it is non-zero range, and the variable info->ranges indicates the number of non-zero ranges. However, in cxl_hdm_decode_init(), the validation for info->dvsec_range[] occurs in a for loop that iterates based on info->ranges. It may result in zero range to be validated but non-zero range not be validated, in turn, the number of allowed ranges is to be 0. Address it by only record non-zero ranges. This fix is not urgent as it requires a configuration that zeroes out the first dvsec range while populating the second. This has not been observed, but it is theoretically possible. If this gets picked up for -stable, no harm done, but there is no urgency to backport. Fixes: 560f78559006 ("cxl/pci: Retrieve CXL DVSEC memory info") Reviewed-by: Jonathan Cameron Signed-off-by: Yanfei Xu Reviewed-by: Alison Schofield Link: https://patch.msgid.link/20240828084231.1378789-2-yanfei.xu@intel.com Signed-off-by: Dave Jiang --- diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c index 5e5c24eed545b..075a2b2d2ea0e 100644 --- a/drivers/cxl/core/pci.c +++ b/drivers/cxl/core/pci.c @@ -390,10 +390,6 @@ int cxl_dvsec_rr_decode(struct device *dev, int d, size |= temp & CXL_DVSEC_MEM_SIZE_LOW_MASK; if (!size) { - info->dvsec_range[i] = (struct range) { - .start = 0, - .end = CXL_RESOURCE_NONE, - }; continue; } @@ -411,12 +407,10 @@ int cxl_dvsec_rr_decode(struct device *dev, int d, base |= temp & CXL_DVSEC_MEM_BASE_LOW_MASK; - info->dvsec_range[i] = (struct range) { + info->dvsec_range[ranges++] = (struct range) { .start = base, .end = base + size - 1 }; - - ranges++; } info->ranges = ranges;