Q:

An unexpected mushroom in my garden

My grandma is a great fan of mushrooms and knows quite a lot about them. About 10 years ago, she started throwing out mushroom remnants in one special place, in order to grow her own mushrooms. In fact, for last three years we found some parasol mushrooms (Macrolepiota procera).
Today she found something, that nobody at home can classify. From what I searched, it might be  Cortinarius privignoides, but it is marked as almost extinct here in Poland, so I doubt this classification. Maybe you have seen this or know what it really is:

The hat is light brown with faint violet shades, the leg on the outside is partly violet too, but the inside is all white.
Some more photos:
All three
The gills are lighter brown, also with a violet tone
The cut through the leg
The cut through the hat
At my parents' house I found one more mushroom atlas, and a new candidate: Cortinarius traganus, but one thing is not right - the ones that I have don't have a smell and gassy webcap should smell and taste bad.

A:

Thanks to MCM's advice I know for almost-certain that this is Lepista personata.

